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Farr NTH, Workman VL, Saad S, Roman S, Hearnden V, Chapple CR, Murdoch C, Rodenburg C, MacNeil S. Uncovering the relationship between macrophages and polypropylene surgical mesh. Biomater Adv 2024; 159:213800. [PMID: 38377947 DOI: 10.1016/j.bioadv.2024.213800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 02/06/2024] [Accepted: 02/11/2024] [Indexed: 02/22/2024]
Abstract
Currently, in vitro testing examines the cytotoxicity of biomaterials but fails to consider how materials respond to mechanical forces and the immune response to them; both are crucial for successful long-term implantation. A notable example of this failure is polypropylene mid-urethral mesh used in the treatment of stress urinary incontinence (SUI). The mesh was largely successful in abdominal hernia repair but produced significant complications when repurposed to treat SUI. Developing more physiologically relevant in vitro test models would allow more physiologically relevant data to be collected about how biomaterials will interact with the body. This study investigates the effects of mechanochemical distress (a combination of oxidation and mechanical distention) on polypropylene mesh surfaces and the effect this has on macrophage gene expression. Surface topology of the mesh was characterised using SEM and AFM; ATR-FTIR, EDX and Raman spectroscopy was applied to detect surface oxidation and structural molecular alterations. Uniaxial mechanical testing was performed to reveal any bulk mechanical changes. RT-qPCR of selected pro-fibrotic and pro-inflammatory genes was carried out on macrophages cultured on control and mechanochemically distressed PP mesh. Following exposure to mechanochemical distress the mesh surface was observed to crack and craze and helical defects were detected in the polymer backbone. Surface oxidation of the mesh was seen after macrophage attachment for 7 days. These changes in mesh surface triggered modified gene expression in macrophages. Pro-fibrotic and pro-inflammatory genes were upregulated after macrophages were cultured on mechanochemically distressed mesh, whereas the same genes were down-regulated in macrophages exposed to control mesh. This study highlights the relationship between macrophages and polypropylene surgical mesh, thus offering more insight into the fate of an implanted material than existing in vitro testing.
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Affiliation(s)
- Nicholas T H Farr
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK; Insigneo Institute for in silico Medicine, The Pam Liversidge Building, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK.
| | - Victoria L Workman
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK; Insigneo Institute for in silico Medicine, The Pam Liversidge Building, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK
| | - Sanad Saad
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK; Department of Urology, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - Sabiniano Roman
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK
| | - Vanessa Hearnden
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK; Insigneo Institute for in silico Medicine, The Pam Liversidge Building, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK
| | | | - Craig Murdoch
- School of Clinical Dentistry, 19 Claremont Crescent, University of Sheffield, Sheffield, UK
| | - Cornelia Rodenburg
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK; Insigneo Institute for in silico Medicine, The Pam Liversidge Building, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK
| | - Sheila MacNeil
- Department of Materials Science and Engineering, University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield, UK
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Clausen KU, Pienack N, Gripp J, Tuczek F. Oxidative Decarbonylation of an Azacalixpyridine-Supported Mo(0)-Tricarbonyl to a Mo(VI)-Trioxo Complex with Dioxygen in Solution and on Au(111): Determination of Molecular Mechanism. Chemistry 2024; 30:e202304359. [PMID: 38305666 DOI: 10.1002/chem.202304359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 01/31/2024] [Accepted: 01/31/2024] [Indexed: 02/03/2024]
Abstract
The conversion of an azacalixpyridine-supported Mo(0) tricarbonyl into a Mo(VI) trioxo complex with dioxygen (O2) is investigated in homogeneous solution and in a molecular film adsorbed on Au(111) using a variety of spectroscopic and analytical methods. These studies in particular show that the dome-shaped carbonyl complex adsorbed on the metal surface has the ability to bind and activate gaseous oxygen, overcoming the so-called surface trans-effect. Furthermore, the rate of the conversion dramatically increases by irradiation with light. This observation is explained with the help of complementary DFT calculations and attributed to two different pathways, a thermal and a photochemical one. Based on the experimental and theoretical findings, a molecular mechanism for the conversion of the carbonyl to the oxo complex is derived.
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Affiliation(s)
- Kai Uwe Clausen
- Institute of Inorganic Chemistry, Christian-Albrechts-University of Kiel, Max-Eyth Straße 2, 24118, Kiel, Germany
| | - Nicole Pienack
- Institute of Inorganic Chemistry, Christian-Albrechts-University of Kiel, Max-Eyth Straße 2, 24118, Kiel, Germany
| | - Joachim Gripp
- Institute of Physical Chemistry, Christian-Albrechts-University of Kiel, Max-Eyth Straße 1, 24118, Kiel, Germany
| | - Felix Tuczek
- Institute of Inorganic Chemistry, Christian-Albrechts-University of Kiel, Max-Eyth Straße 2, 24118, Kiel, Germany
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Muthukumar B, Satheeshkumar A, Parthipan P, Laishram B, Duraimurugan R, Devanesan S, AlSalhi MS, Rajamohan R, Rajasekar A. Integrated approach of nano assisted biodegradation of anthracene by Pseudomonas aeruginosa and iron oxide nanoparticles. Environ Res 2024; 244:117911. [PMID: 38104919 DOI: 10.1016/j.envres.2023.117911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 11/29/2023] [Accepted: 12/09/2023] [Indexed: 12/19/2023]
Abstract
Poly aromatic hydrocarbons (PAHs) are considered as hazardous compounds which causes serious threat to the environment dua to their more carcinogenic and mutagenic impacts. In this study, Pseudomonas aeruginosa PP4 strain and synthesized iron nanoparticles were used to evaluate the biodegradation efficiency (BE %) of residual anthracene. The BE (%) of mixed degradation system (Anthracene + PP4+ FeNPs) was obtained about 67 %. The FTIR spectra result revealed the presence of functional groups (C-H, -CH3, CC, =C-H) in the residual anthracene. The FESEM and TEM techniques were used to determine the surface analysis of the synthesized FeNPs and the average size was observed by TEM around 5-50 nm. The crystalline nature of the synthesized iron nanoparticles was confirmed by the observed different respective peaks of XRD pattern. The various functional constituents (OH, C-H, amide I, CH3) were identified in the synthesized iron nanoparticles by FTIR spectrum. In conclusion, this integrated nano-bioremediation approach could be an promising and effective way for many environmental fields like cleanup of hydrocarbon rich environment.
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Affiliation(s)
- Balakrishnan Muthukumar
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore, Tamil Nadu, 632115, India
| | - Azhagarsamy Satheeshkumar
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore, Tamil Nadu, 632115, India
| | - Punniyakotti Parthipan
- Department of Biotechnology, Faculty of Science and Humanities, SRM Institute of Science and Technology, Kattankulathur, Chengalpattu, Tamil Nadu, 603 203, India
| | - Bibek Laishram
- Department of Agronomy, Assam Agricultural University, Jorhat, 785013, Assam, India
| | - Ramanathan Duraimurugan
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore, Tamil Nadu, 632115, India
| | - Sandhanasamy Devanesan
- Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box-2455, Riyadh, 11451, Saudi Arabia
| | - Mohamad S AlSalhi
- Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box-2455, Riyadh, 11451, Saudi Arabia
| | - Rajaram Rajamohan
- Organic Materials Synthesis Lab, School of Chemical Engineering, Yeungnam University, Gyeongsan-si, 38541, Republic of Korea.
| | - Aruliah Rajasekar
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore, Tamil Nadu, 632115, India; Adjunct Faculty, Department of Prosthodontics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Science (SIMATS), Saveetha University, Chennai, 600077, India.
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Lee JW, Park IY, Ogawa T. Design and optimization of a conical electrostatic objective lens of a low-voltage scanning electron microscope for surface imaging and analysis in ultra-high-vacuum environment. Ultramicroscopy 2024; 257:113908. [PMID: 38134559 DOI: 10.1016/j.ultramic.2023.113908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/01/2023] [Accepted: 12/08/2023] [Indexed: 12/24/2023]
Abstract
Low-voltage scanning electron microscopy (LV-SEM) with landing energies below 5 keV has been widely used due to its advantages in mitigating the damage and charging effects to a specimen and enhancing surface information due to small interaction volume of electrons inside a specimen. Additionally, for elemental analysis of the surfaces of bulk specimens with Auger electron spectroscopy (AES) or electron energy loss spectroscopy (EELS), ultra-high-vacuum (UHV) environment is essential to maintain clean surfaces without the absorption of gas molecules during the electron beam irradiation for the acquisition of spectral data. In this study, we propose the optimal design and condition of a conical Electrostatic Objective Lens (EOL) for a UHV LV-SEM to achieve the high spatial resolution and secondary electron (SE) detection efficiency. The EOL is composed of only the three electrodes (retarding, focusing and booster electrodes) and the insulators, which is suitable for maintaining a UHV environment with less out-gassing. The cone angle of the EOL is determined as 60° to integrate a spectrometer in the UHV LV-SEM and in a large size and a higher tilt angle of the sample. Through the optimization with the simulations, the EOL achieves the minimized spherical and chromatic aberration coefficients of 0.05 and 0.03 mm at the sample side, respectively, at the landing energy of 50 eV and the shortest working distance (WD) of 1 mm for high-resolution imaging. In addition, the probe diameter of the optimized EOL is 2.3 nm at 1 keV and 5.7 nm at 50 eV with a WD of 1 mm and a probe current of 10 pA, which are comparable to previously studied compound objective lenses with magnetic and electrostatic lenses. Using a longer WD of 4 mm for analysis, the probe diameter was 5.4 nm at 1 keV and the SE detection efficiency was 83.3 % owing to the separated scintillator detector structure from the booster electrode. These results imply that the optimized EOL has the potential to be applied to a high-performance UHV LV-SEM for the surface imaging and analysis with a simple system configuration.
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Affiliation(s)
- Jeong-Woong Lee
- Scientific Instruments Performance Evaluation Team, Advanced Instrumentation Institute, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea
| | - In-Yong Park
- Scientific Instruments Performance Evaluation Team, Advanced Instrumentation Institute, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea; Major in Nanoconvergence Measurement, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea; Graduate School of Analytical Science and Technology, Chungnam Nationl University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea
| | - Takashi Ogawa
- Scientific Instruments Performance Evaluation Team, Advanced Instrumentation Institute, Korea Research Institute of Standards and Science (KRISS), 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea; Major in Nanoconvergence Measurement, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea.
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5
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Sharma R, Putera KH, Banaszak Holl MM, Garnier G, Haritos VS. Modulating the hydrophobicity of cellulose by lipase-catalyzed transesterification. Int J Biol Macromol 2024; 254:127972. [PMID: 37944725 DOI: 10.1016/j.ijbiomac.2023.127972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 08/06/2023] [Accepted: 11/06/2023] [Indexed: 11/12/2023]
Abstract
The production of hydrophobic and oil resistant cellulosic fibers usually requires severe chemical treatments and generates toxic by-products. Alternative approaches such as biocatalysis use milder conditions; lipase-catalyzed methods for grafting nanocellulose with hydrophobic ester moieties have been reported. Here, we investigate the lipase-catalyzed esterification of cellulose fibers, in native form or pretreated with 1,4-β-glucanases, and cellulose nanocrystals (CNC) in solvent-free conditions. The fibers were compared for degree of ester formation after incubation with methyl myristate and lipase at 50 °C. After washing, the grafting of fatty esters on cellulose was confirmed by ATR-FTIR and the degree of substitution determined by 13C CP/MAS NMR (from 0.04 up to DS 0.1) confirming successful esterification. Optical photothermal infrared (O-PTIR) spectroscopy showed strongly localized presence of ester moieties on cellulose. Functional properties mirrored the degree of substitution of the cellulose materials whereby cellulose esters made with glucanase-pretreatment produced the highest water contact angle of 117° ± 9 and esterified cellulose blended at 10 % w/w content in paper composites showed significant differences in hydrophobicity and lipophilicity compared to plain paper. The esterification of cellulose was completely reversed by lipase treatment in aqueous media. These ester-functionalized fibers show potential in a wide range of packaging applications.
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Affiliation(s)
- Rahul Sharma
- Bioresource Processing Research Institute of Australia, Department of Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Kevin H Putera
- Bioresource Processing Research Institute of Australia, Department of Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Mark M Banaszak Holl
- Bioresource Processing Research Institute of Australia, Department of Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia; Department of Mechanical and Materials Engineering, University of Alabama at Birmingham, USA
| | - Gil Garnier
- Bioresource Processing Research Institute of Australia, Department of Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - Victoria S Haritos
- Bioresource Processing Research Institute of Australia, Department of Chemical and Biological Engineering, Monash University, Melbourne, Victoria 3800, Australia.
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Dart A, Sarviya N, Babaie A, Clare J, Bhave M, Sumer H, de Haan JB, Giri J, Kingshott P. Highly active nisin coated polycaprolactone electrospun fibers against both Staphylococcus aureus and Pseudomonas aeruginosa. Biomater Adv 2023; 154:213641. [PMID: 37804685 DOI: 10.1016/j.bioadv.2023.213641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/17/2023] [Accepted: 09/25/2023] [Indexed: 10/09/2023]
Abstract
In this study, a wound dressing of electrospun polycaprolactone (PCL) fibers incorporating the antimicrobial peptide (AMP) nisin was fabricated. Nisin was physically adsorbed to the PCL fibers and tested for antibacterial activity against both Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa). The PCL fibers had an average diameter of 1.16 μm ± 0.42 μm and no significant change in diameter occurred after nisin adsorption. X-ray photoelectron spectroscopy (XPS) analysis of the fibers detected nitrogen indicative of adsorbed nisin and the signal was used to quantify the levels of coverage on the fiber surfaces. In vitro nisin release studies showed a burst release profile with 80 % of the nisin being released from the fibers within 30 min. Air plasma pre-treatment of the PCL fibers to render them hydrophilic improved nisin loading and release. Antibacterial testing was performed using minimum inhibitory concentration (MIC) and surface attachment assays. The released nisin remained active against both Gram positive S. aureus and Gram negative P. aeruginosa, which has previously been difficult to achieve with single polymer fiber systems. Mammalian cell culture of the nisin coated fibers with L-929 mouse fibroblasts and human epidermal keratinocytes (HEKa) showed that the nisin did not have a significant effect on the biocompatibility of the PCL fibers. The results presented here demonstrate that the physical adsorption, which is a post-treatment, overcomes the potential limitations of harsh chemicals and fabrication conditions of electrospinning from organic solvents and provides a drug loading system having effective antibacterial properties in wound dressings.
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Affiliation(s)
- Alexander Dart
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Nandini Sarviya
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Ali Babaie
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Jessie Clare
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia; Baker Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Mrinal Bhave
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Huseyin Sumer
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia
| | - Judy B de Haan
- Baker Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Jyotsnendu Giri
- Department of Biomedical Engineering, Indian Institute of Technology, Hyderabad, India
| | - Peter Kingshott
- Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn, Victoria 3122, Australia; ARC Training Centre Training Centre in Surface Engineering for Advanced Materials (SEAM), Swinburne University of Technology, Hawthorn, Victoria 3122, Australia.
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Huang LL, Chua ZQ, Buchowiecki K, Raju CM, Urban PL. Hydrogel-enzyme micropatch array format for chemical mapping: A proof of concept. Biosens Bioelectron 2023; 239:115599. [PMID: 37611447 DOI: 10.1016/j.bios.2023.115599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/06/2023] [Accepted: 08/12/2023] [Indexed: 08/25/2023]
Abstract
Conventional sensing methods report on concentrations of analytes in a single point of sampled medium or provide an average value. However, distributions of substances on surfaces of sampled objects often exhibit intricate inhomogeneities. In order to obtain snapshots of the chemical distributions on surfaces, we have developed enzyme-loaded hydrogel arrays (5 × 5 and 10 × 10). The acrylic 10 × 10 array base contains 100 holes, which are filled with agarose hydrogel containing assay enzymes and substrates. Such arrays can be exposed to the analyzed surfaces to collect minute amounts of analytes. Following a brief incubation, they are subsequently visualized in a custom-built array reader device. The reader incorporates a light-emitting diode-based light source, miniature camera, and Raspberry Pi single-board computer. Two Python programs capture and analyze the images of the array to extract pixel saturation values corresponding to individual hydrogel micropatches. The method has been thoroughly optimized for mapping of glucose and lactic acid. The optimized parameters were: contact time, agarose concentration, substrate concentration, enzyme concentration ratio, and enzyme concentration. The array biosensor was further tested by mapping glucose distribution in fruit/vegetable cross-sections (apple, guava, and cucumber) and lactic acid distribution in cheese. We think that this new hydrogel-based chemical mapping method can find applications in studies related to food science, plant physiology, clinical chemistry, and forensics; wherever the distributions of analytes on the tested surfaces need to be assessed.
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Affiliation(s)
- Li-Li Huang
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan
| | - Zi Qing Chua
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan
| | - Krzysztof Buchowiecki
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan
| | - Chamarthi Maheswar Raju
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan
| | - Pawel L Urban
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan; Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, 101, Section 2, Kuang-Fu Rd., Hsinchu, 300044, Taiwan.
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Mai A, Hadnagy E, Shi Q, Ezeonu L, Robbins JP, Podkolzin SG, Koutsospyros A, Christodoulatos C. Degradation and fate of 2,4-dinitroanisole (DNAN) and its intermediates treated with Mg/Cu bimetal: Surface examination with XAS, DFT, and LDI-MS. J Environ Sci (China) 2023; 129:161-173. [PMID: 36804233 DOI: 10.1016/j.jes.2022.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 06/18/2023]
Abstract
A novel Mg-based bimetal reagent (Mg/Cu) was used as an enhanced reductive system to degrade insensitive munition 2,4-dinitroanisole (DNAN), a contaminant found in energetic-laden waste. Degradation of DNAN was significantly impacted by dissolved oxygen and studied in anoxic and oxic bimetal systems (i.e., purging with N2, air, or O2 gas). Degradation occurred through sequential nitroreduction: first one nitro group was reduced (ortho or para) to form short-lived intermediates 2-amino-4-nitroanisole or 4-amino-2-nitroanisole (2-ANAN or 4-ANAN), and then subsequent reduction of the other nitro group formed 2,4-diaminoanisole (DAAN). The nitro-amino intermediates demonstrated regioselective reduction in the ortho position to 2-ANAN; Regioselectivity was also impacted by the anoxic/oxic environment. Under O2-purging DNAN degradation rate was slightly enhanced, but most notably O2 significantly accelerated DAAN generation. DAAN also further degraded only in the oxygenated Mg/Cu system. Adsorption of DNAN byproducts to the reagent occurred regardless of anoxic/oxic condition, resulting in a partition of carbon mass between the adsorbed phase (27%-35%) and dissolved phase (59%-72%). Additional surface techniques were applied to investigate contaminant interaction with Cu. Density functional theory (DFT) calculations identified preferential adsorption structures for DNAN on Cu with binding through two O atoms of one or both nitro groups. X-ray absorption spectroscopy (XAS) measurements determined the oxidation state of catalytic metal Cu and formation of a Cu-O-N bond during treatment. Laser desorption ionization mass spectrometry (LDI-MS) measurements also identified intermediate 2-ANAN adsorbed to the bimetal surface.
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Affiliation(s)
- Andrew Mai
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
| | - Emese Hadnagy
- School of Engineering and Technology, University of Washington Tacoma, Tacoma, WA 98402, USA
| | - Qiantao Shi
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, USA
| | - Lotanna Ezeonu
- School of Engineering and Technology, University of Washington Tacoma, Tacoma, WA 98402, USA
| | - Jason P Robbins
- School of Engineering and Technology, University of Washington Tacoma, Tacoma, WA 98402, USA
| | - Simon G Podkolzin
- School of Engineering and Technology, University of Washington Tacoma, Tacoma, WA 98402, USA
| | - Agamemnon Koutsospyros
- Center for Environmental Systems, Stevens Institute of Technology, Hoboken, NJ 07030, USA
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Feng X, Chen Z, Wang S, Cen L, Ni BJ, Liu Q. Insights into the weathering behavior of pyrite in alkaline soil through electrochemical characterizations: Actual hazards or potentially benefits? J Hazard Mater 2023; 451:131145. [PMID: 36889071 DOI: 10.1016/j.jhazmat.2023.131145] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 02/07/2023] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Pyrite is the most common metal sulfide mineral in the crust and readily weathers under natural circumstances to release H+ to acidify surrounding groundwater and soil, resulting in heavy metal ions in the surrounding environment (e.g., meadow and saline soils). Meadow and saline soils are two common, widely distributed alkaline soils and can affect pyrite weathering. Currently, the weathering behaviors of pyrite in saline and meadow soil solutions have not been systematically studied. Electrochemistry coupled with surface analysis methods were employed to study pyrite weathering behaviors in simulated saline and meadow soil solutions in this work. Experimental results suggest that saline soil and higher temperatures increase pyrite weathering rates due to the lower resistance and greater capacitance. Surface reactions and diffusion control the weathering kinetics, and the activation energies for the simulated meadow and saline soil solutions are 27.1 and 15.8 kJ mol-1, respectively. In-depth investigations reveal that pyrite is initially oxidized to Fe(OH)3 and S0, and Fe(OH)3 further transforms into goethite γ-FeOOH and hematite α-Fe2O3, while S0 ultimately converts into sulfate. When these iron compounds enter alkaline soils, the alkalinity of soil changes, and iron (hydr)oxides effectively reduce the bioavailability of heavy metals and benefit alkaline soils. Meanwhile, weathering of natural pyrite ores containing toxic elements (such as Cr, As, and Cd) makes these elements bioavailable and potentially degrades the surrounding environment.
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Affiliation(s)
- Xiaonan Feng
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Zhijie Chen
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Shuai Wang
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Ling Cen
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Qingyou Liu
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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Unterschütz L, Fuchs F, Mayer LA, Koenig A, Challakh N, Schulz-Kornas E, Ziebolz D, Hahnel S. Influence of dental prophylaxis procedures on the tooth veneer interface in resin-based composite and polymer-infiltrated ceramic veneer restorations: an in vitro study. Clin Oral Investig 2023; 27:2595-2607. [PMID: 36502509 PMCID: PMC10264478 DOI: 10.1007/s00784-022-04816-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/30/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVES The aim of this study was to investigate the influence of dental prophylaxis cleaning procedures and artificial aging on veneers in human teeth. The external marginal and internal tooth veneer as well as the restoration surfaces were examined. MATERIAL AND METHODS Thirty-two extracted premolars were restored with resin-based composite (RBC) and polymer-infiltrated ceramic network (PICN) veneers. Artificial aging by alternating thermocycling and subsequent prophylaxis procedure (glycine-based powder air polishing or ultrasonic scaling) was conducted for five consecutive cycles. The external marginal interface was examined by height profile measurements and the internal interface was investigated using micro X-ray computed tomography. In addition, the surface texture of the veneer surface was analyzed using confocal laser scanning microscopy. RESULTS The application of both prophylaxis procedures resulted in a deepening of the marginal interface (10 µm ± 8 µm) for materials. Furthermore, the internal interface of PICN restorations showed marginal gaps after both treatments and artificial aging (16 µm ± 3 µm). In contrast to the RBC specimens, a significant increase in surface roughness was identified for PICN veneers after ultrasonic scaling. CONCLUSIONS The marginal and internal interface regions in veneers fabricated from PICN and RBC were affected by prophylaxis procedures. Furthermore, it may result in increased veneer surface roughness, especially in PICN and after ultrasonic scaling, which might affect bioadhesion and longevity. CLINICAL RELEVANCE After dental prophylaxis procedures, examination of the marginal and the internal interface as well as the veneer surface provides a precise insight into damage mechanisms and offers an assessment of longevity.
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Affiliation(s)
- Lena Unterschütz
- Department of Prosthetic Dentistry and Dental Material Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Florian Fuchs
- Department of Prosthetic Dentistry and Dental Material Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany.
| | - Laura-Antonia Mayer
- Department of Prosthetic Dentistry and Dental Material Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Andreas Koenig
- Department of Prosthetic Dentistry and Dental Material Science, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Nadia Challakh
- Department of Cariology, Endodontology and Periodontology, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Ellen Schulz-Kornas
- Department of Cariology, Endodontology and Periodontology, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Dirk Ziebolz
- Department of Cariology, Endodontology and Periodontology, Leipzig University, Liebigstraße 12, 04103, Leipzig, Germany
| | - Sebastian Hahnel
- Department of Prosthetic Dentistry, UKR University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany
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11
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Salas A, Berrio ME, Martel S, Díaz-Gómez A, Palacio DA, Tuninetti V, Medina C, Meléndrez MF. Towards recycling of waste carbon fiber: Strength, morphology and structural features of recovered carbon fibers. Waste Manag 2023; 165:59-69. [PMID: 37086657 DOI: 10.1016/j.wasman.2023.04.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 03/29/2023] [Accepted: 04/09/2023] [Indexed: 05/03/2023]
Abstract
Carbon fiber is one of the most widely used materials in high demand applications due to its high specific properties, however, its post-recycling properties limit its use to low performance applications. In this research, the carbon fiber recovering is examined using two methods: two-step pyrolysis and microwave-assisted thermolysis. The results indicate that the fibers recovered by pyrolysis show reduced surface and structural damage, maintaining the original mechanical properties of the fiber with losses below 5%. The fibers recovered by microwaves undergo significant surface changes that reduce their tensile strength by up to 60% and changes in their graphitic structure, increasing their degree of crystallinity by Raman index ID/IG from 1.98 to 2.86 and their amorphous degree by ID"/IG ratio from 0.411 to 1.599. Recovering fibers from microwave technique is 70% faster compared to two step pyrolysis, and provides recycled fibers with superior surface activation with the presence of polar functional groups -OH, -CO, and -CH that react with the epoxy matrix. The thermal, morphological, structural and mechanical characterizations of the recovered fibers detailed in this work provide valuable findings to evaluate their direct reuse in new composite materials.
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Affiliation(s)
- A Salas
- Interdisciplinary Group of Applied Nanotechnology (GINA), Hybrid Materials Laboratory (HML), Department of Materials Engineering (DIMAT), Faculty of Engineering, University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile; Department of Mechanical Engineering (DIM), Faculty of Engineering, University of Concepción, 219 Edmundo Larenas, Concepcion 4070409, Chile
| | - M E Berrio
- Interdisciplinary Group of Applied Nanotechnology (GINA), Hybrid Materials Laboratory (HML), Department of Materials Engineering (DIMAT), Faculty of Engineering, University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile
| | - S Martel
- Department of Mechanical Engineering (DIM), Faculty of Engineering, University of Concepción, 219 Edmundo Larenas, Concepcion 4070409, Chile
| | - A Díaz-Gómez
- Interdisciplinary Group of Applied Nanotechnology (GINA), Hybrid Materials Laboratory (HML), Department of Materials Engineering (DIMAT), Faculty of Engineering, University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile
| | - Daniel A Palacio
- Department of Polymers, Faculty of Chemistry, University of Concepción, Concepción, Chile
| | - V Tuninetti
- Department of Mechanical Engineering, Universidad de La Frontera, Francisco Salazar 01145, Temuco 4780000, Chile.
| | - C Medina
- Department of Mechanical Engineering (DIM), Faculty of Engineering, University of Concepción, 219 Edmundo Larenas, Concepcion 4070409, Chile
| | - M F Meléndrez
- Interdisciplinary Group of Applied Nanotechnology (GINA), Hybrid Materials Laboratory (HML), Department of Materials Engineering (DIMAT), Faculty of Engineering, University of Concepcion, 270 Edmundo Larenas, Box 160-C, Concepcion 4070409, Chile.
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12
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Borowska M, Jankowski K. Basic and advanced spectrometric methods for complete nanoparticles characterization in bio/eco systems: current status and future prospects. Anal Bioanal Chem 2023:10.1007/s00216-023-04641-7. [PMID: 36949345 PMCID: PMC10329056 DOI: 10.1007/s00216-023-04641-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/27/2023] [Accepted: 03/03/2023] [Indexed: 03/24/2023]
Abstract
The use of engineered nanoparticles in the environment and human life has increased in the last 20 years. The risk assessment concerning application of nanomaterials in biological systems requires their thorough characterization. Understanding the correlations between physicochemical properties of nanoparticles concerning not only the size, particle size distribution, number concentration, degree of aggregation, or agglomeration but also solubility, stability, binding affinity, surface activity, chemical composition, and nanoparticle synthesis yield allows their reliable characterization. Thus, to find the structure-function/property relationship of nanoparticles, multifaceted characterization approach based on more than one analytical technique is required. On the other hand, the increasing demand for identification and characterization of nanomaterials has contributed to the continuous development of spectrometric techniques which enables for their qualitative and quantitative analysis in complex matrices giving reproducible and reliable results. This review is aimed at providing a discussion concerning four main aspects of nanoparticle characterization: nanoparticle synthesis yield, particle size and number concentration, elemental and isotopic composition of nanoparticles, and their surface properties. The conventional and non-conventional spectrometric techniques such as spectrophotometry UV-Vis, mass spectrometric techniques working in conventional and single-particle mode, or those based on optical emission detection systems are described with special emphasis paid on their advantages and drawbacks. The application and recent advances of these methods are also comprehensively reviewed and critically discussed.
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Affiliation(s)
- Magdalena Borowska
- Chair of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw, 00-664, Poland.
| | - Krzysztof Jankowski
- Chair of Analytical Chemistry, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, Warsaw, 00-664, Poland
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13
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Proniewicz E. Metallic nanoparticles as effective sensors of bio-molecules. Spectrochim Acta A Mol Biomol Spectrosc 2023; 288:122207. [PMID: 36502763 DOI: 10.1016/j.saa.2022.122207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/23/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
This work describes biologically important nanostructures of metals (AgNPs, AuNPs, and PtNPs) and metal oxides (Cu2ONPs, CuONSs, γ-Fe2O3NPs, ZnONPs, ZnONPs-GS, anatase-TiO2NPs, and rutile-TiO2NPs) synthesized by different methods (wet-chemical, electrochemical, and green-chemistry methods). The nanostructures were characterized by molecular spectroscopic methods, including scanning/transmission electron microscopy (SEM/TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis), dynamic light scattering (DLS), Raman scattering spectroscopy (RS), and infrared light spectroscopy (IR). Then, a peptide (bombesin, BN) was adsorbed onto the surface of these nanostructures from an aqueous solution with pH of 7 that did not contain surfactants. Adsorption was monitored using surface-enhanced Raman scattering spectroscopy (SERS) to determine the influence of the nature of the metal surface and surface evolution on peptide geometry. Information from the SERS studies was compared with information on the biological activity of the peptide. The SERS enhancement factor was determined for each of the metallic surfaces.
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Affiliation(s)
- E Proniewicz
- Faculty of Foundry Engineering, AGH University of Science and Technology, 30-059 Krakow, Poland.
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14
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Moimane T, Peng Y. Sulphidisation of oxides and oxidised sulphides and adsorption of thiol collectors on the sulphidised products-a critical review. Adv Colloid Interface Sci 2022; 305:102697. [PMID: 35609399 DOI: 10.1016/j.cis.2022.102697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/10/2022] [Accepted: 05/10/2022] [Indexed: 11/28/2022]
Abstract
Sulphidisation, an electrochemical process for conversion of a non-sulphide, oxide or oxidised sulphide, to a sulphide surface that facilitates efficient adsorption of thiol collectors to impart hydrophobicity, offers a way to improve the enrichment of oxide and oxidised sulphide ores by flotation. Although it has shown great potential, it has equally proved to suffer from drawbacks such as low efficiency, difficulty to sulphidise minerals that are prone to surface oxidation and the chemistry at play remains insufficiently understood. These drawbacks hinder the full potential of the sulphidisation process as a remediation strategy for flotation of oxide and oxidised sulphide ores. A holistic understanding of the process is crucial in identification of the underpinning phenomena that render the process inefficient and will be a stepping stone in the quest to modify it for an improved efficiency. Therefore, this paper seeks to review the sulphidisation reactions and products at the mineral-solution interfaces of oxide and oxidised sulphide minerals. The influence and implications of the sulphidisation conditions on adsorption of thiol collectors on mineral surfaces to impart hydrophobicity necessary for flotation are also highlighted. Finally, it makes recommendations on how to circumvent the drawbacks and provides guidelines for future research and industrial application.
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Affiliation(s)
- Tiisetso Moimane
- School of Chemical Engineering, The University of Queensland, St Lucia, Brisbane, QLD 4072, Australia
| | - Yongjun Peng
- School of Chemical Engineering, The University of Queensland, St Lucia, Brisbane, QLD 4072, Australia.
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15
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Fadillah G, Saleh TA, Munawaroh H, Wahyuningsih S, Ramelan AH. Flow photocatalysis system-based functionalized graphene oxide-ZnO nanoflowers for degradation of a natural humic acid. Environ Sci Pollut Res Int 2022; 29:9883-9891. [PMID: 34508317 DOI: 10.1007/s11356-021-16333-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/31/2021] [Indexed: 06/13/2023]
Abstract
The functionalized graphene oxide-ZnO (fGO/ZnO) nanoflower composites have been studied as a photocatalyst material for flow photodegradation of humic acid (HA) in real samples. The fGO/ZnO nanoflower was prepared via hydrothermal methods. The chemical and physical properties of the synthesized photocatalyst have been carried out by several techniques, including X-ray diffraction (XRD), scanning electron microscope-energy-dispersive spectrometer (SEM-EDS), Fourier transform infrared (FTIR), and UV-Vis spectrophotometer. The photocatalytic study of degradation of HA by flow system is reported. The optimum condition for degradation was found at pH 4.0, a flow rate of 1 mL min-1, and a light intensity of 400 mW cm-2. The degradation efficiency of HA also was influenced by several anion or cation concentration ratios on the system. This method was applied for the degradation of HA in extracted natural HA from the soil, and the efficiency achieved at 98.5%. Therefore, this research provides a low-cost, fast, and reusability method for HA degradation in the environment.
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Affiliation(s)
- Ganjar Fadillah
- Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Islam Indonesia, Yogyakarta, 55584, Indonesia
| | - Tawfik A Saleh
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
| | - Hanik Munawaroh
- Inorganic Material Research Group, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret, Surakarta, 57126, Indonesia
| | - Sayekti Wahyuningsih
- Inorganic Material Research Group, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret, Surakarta, 57126, Indonesia
| | - Ari Handono Ramelan
- Inorganic Material Research Group, Faculty of Mathematics and Natural Sciences, Universitas Sebelas Maret, Surakarta, 57126, Indonesia
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16
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Feng X, Liu Q, Wang S, Cen L, Li H. Arsenopyrite weathering in acid rain: Arsenic transfer and environmental implications. J Hazard Mater 2021; 420:126612. [PMID: 34265655 DOI: 10.1016/j.jhazmat.2021.126612] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 07/05/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
Arsenopyrite is widely distributed and weathers readily in the nature, releases As and pollutes the surrounding environment. Acid rain is acidic in nature as contains sulfur oxides (SOx) and nitrogen oxides (NOx), and is a typical hazardous material to human. When arsenopyrite encounters acid rain, their interaction effect may aggregate environmental degradation. In this work, the weathering behavior of arsenopyrite in simulated acid rain was studied using the electrochemical techniques and surface analysis. Cyclic voltammetry and Raman and XPS confirmed that FeAsS was oxidized to Fe2+, AsO33- and S0 at the initial phase, then, Fe2+ was converted to Fe3+, S0 transformed to SO32- and ultimately to SO42-, and AsO33- to AsO43- with the accumulation of H+. Polarization curve revealed higher temperature or higher acidity of acid rain increased the weathering trend and rate of arsenopyrite, and electrochemical impedance spectroscopic measurements showed the causes behind this to be smaller resistance and greater capacitance at the double layer and passivation film. Arsenopyrite weathering rate and temperature has a relationship: lnk = -3824.8/T + 10.305, via a transition state with activation enthalpy 29.37 kJ mol-1 and activation entropy - 167.40 J mol-1 K-1. This study provides a rapid and quantitative in-situ electrochemical method for arsenopyrite weathering and an improved understanding of arsenopyrite weathering in acid rain condition. The results have powerful implications for the remediation and management of As-bearing sites affected by mining activities in acid rain area.
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Affiliation(s)
- Xiaonan Feng
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Qingyou Liu
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Shuai Wang
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Ling Cen
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; University of Chinese Academy of Sciences, Beijing 100039, China
| | - Heping Li
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
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17
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Sathanikan A, Ceccone G, Bañuls-Ciscar J, Pan M, Kamal F, Bsaibess T, Gaucher A, Prim D, Méallet-Renault R, Colpo P, Amigoni S, Guittard F, Darmanin T. A bioinspired approach to fabricate fluorescent nanotubes with strong water adhesion by soft template electropolymerization and post-grafting. J Colloid Interface Sci 2021; 606:236-47. [PMID: 34390991 DOI: 10.1016/j.jcis.2021.08.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/31/2021] [Accepted: 08/02/2021] [Indexed: 11/20/2022]
Abstract
HYPOTHESIS In this original work, we aim to control both the surface wetting and fluorescence properties of extremely ordered and porous conducting polymer nanotubes prepared by soft template electropolymerization and post-grafting. For reaching this aim, various substituents of different hydrophobicity and fluorescence were post-grafted and the post-grafting yields were evaluated by surface analyses. We show that the used polymer is already fluorescent before post-grafting while the post-grafting yield and as a consequence the surface hydrophobicity highly depend on the substituent. EXPERIMENTS Here, we have chosen to chemically grafting various fluorinated and aromatic substituents using a post-grafting in order to keep the same surface topography. Flat conducting polymer surfaces with similar properties have been also prepared for determining the surface energy with the Owens-Wendt equation and estimating the post-grafting yield by X-ray Photoemission Spectroscopy (XPS) and Time of Flight Secondary Emission Spectrometry (ToF-SIMS). For example, using fluorinated chains of various length (C4F9, C6F13 and C8F17), it is demonstrated that the surface hydrophobicity and oleophobicity do not increase with the fluorinated chain length due to the different post-grafting yields and because of the presence of nanoroughness after post-grafting. FINDINGS These surfaces have high apparent water contact angle up to 130.5° but also strong water adhesion, comparable to rose petal effect even if there are no nanotubes on petal surface. XPS and ToF-SIMS analyses provided a detailed characterisation of the surface chemistry with a qualitative classification of the grafted surfaces (F6 > F4 > F8). SEM analysis shows that grafting does not alter the surface morphology. Finally, fluorescence analyses show that the polymer surfaces before post-treatment are already nicely fluorescent. Although the main goal of this paper was and is to understand the role of surface chemistry in tailoring the wetting properties of these surfaces rather than provide specific application examples, we believe that the obtained results can help the development of specific nanostructured materials for potential applications in liquid transport, or in stimuli responsive antimicrobial surfaces.
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Barinov NA, Tolstova AP, Bersenev EA, Ivanov DA, Dubrovin EV, Klinov DV. Molecular patterns of oligopeptide hydrocarbons on graphite. Colloids Surf B Biointerfaces 2021; 206:111921. [PMID: 34157520 DOI: 10.1016/j.colsurfb.2021.111921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 05/19/2021] [Accepted: 06/13/2021] [Indexed: 10/21/2022]
Abstract
Graphitic materials including graphene, carbon nanotubes and fullerenes, are promising for use in nanotechnology and biomedicine. Non-covalent functionalization by peptides and other organic molecules allows changing the properties of graphitic surfaces in a controlled manner and represents a big potential for fundamental research and applications. Recently described oligopeptide-hydrocarbon derivative N,N'-(decane-1,10-diyl)bis(tetraglycineamide) (GM) is highly prospective for the development of graphitic interfaces in biosensor application as well as in structural biology for improving the quality of high-resolution atomic force microscopy (AFM) visualization of individual biomacromolecules. However, molecular organization of GM on graphitic surfaces is still unknown. In this work, the molecular model of GM at the water/highly oriented pyrolytic graphite (HOPG) interface has been developed basing on the high-resolution AFM and full-atom molecular modeling data. This model explains two periodicities observed in AFM images by GM self-assembly on a HOPG surface with formation of the stacks with the lateral shifts. The obtained results reveal the particular patterns and dynamics of GM molecules adsorbed on graphite and unravel the puzzle of peptide self-assembly on graphitic surfaces.
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Affiliation(s)
- Nikolay A Barinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation
| | - Anna P Tolstova
- Engelhardt Institute of Molecular Biology, Vavilova 32, 119991, Moscow, Russian Federation
| | - Egor A Bersenev
- Moscow Institute of Physics and Technology, Institutskiy Per. 9, Dolgoprudny 141700, Russian Federation; Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Russian Federation
| | - Dmitry A Ivanov
- Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation; Institut de Sciences des Matériaux de Mulhouse-IS2M, CNRS UMR 7361, 15, rue Jean Starcky, F-68057 Mulhouse, France
| | - Evgeniy V Dubrovin
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Lomonosov Moscow State University, Leninskie Gory 1 Bld. 2, 119991 Moscow, Russian Federation.
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Malaya Pirogovskaya 1a, Moscow 119435 Russian Federation; Sirius University of Science and Technology, 1 Olympic Ave, 354340, Sochi, Russian Federation.
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Coorens NA, Daemen JHT, Slump CH, Loonen TGJ, Vissers YLJ, Hulsewé KWE, de Loos ER. The Automatic Quantification of Morphological Features of Pectus Excavatum Based on Three-Dimensional Images. Semin Thorac Cardiovasc Surg 2021; 34:772-781. [PMID: 34102293 DOI: 10.1053/j.semtcvs.2021.05.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 05/11/2021] [Indexed: 12/16/2022]
Abstract
Visual examination and quantification of severity are essential for clinical decision making in patients with pectus excavatum. Yet, visual assessment is prone to inter- and intra-observer variability and current quantitative methods are inadequate. This study aims to develop and evaluate a novel, automatic and non-invasive method to objectively quantify pectus excavatum morphology based on three-dimensional images. Key steps of the automatic analysis are normalization of image orientation, slicing, and computation of the morphological features encompassing pectus depth, width, length, volume, position, steepness, flaring, asymmetry and mean cross-sectional area. A digital phantom mimicking a patient with pectus excavatum was used to verify the analysis method. Prospective three-dimensional imaging and subsequent surface analysis in patients with pectus excavatum was performed to assess clinical feasibility. Verification of the developed analysis tool demonstrated 100% reproducibility of all morphological feature values. Calculated parameters compared to the predetermined phantom dimensions were accurate for all but four features. The pectus width, length, volume and steepness showed an error of 4 mm (4%), 2 mm (2%), 12 mL (5%) and 1 degree (3%), respectively. Prospective imaging of 52 patients (88% males) demonstrated the feasibility of the developed tool to quantify morphological features of pectus excavatum in the clinical setting. Mean duration to calculate all features in one patient was 7.6 seconds. We have developed and presented a non-invasive pectus excavatum surface analysis tool, that is feasible to automatically quantify morphological features based on three-dimensional images with promising accuracy and reproducibility.
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Affiliation(s)
- Nadine A Coorens
- Department of Surgery, Division of General Thoracic Surgery, Zuyderland Medical Center, Heerlen, The Netherlands; Faculty of Science and Technology (S&T), University of Twente, Enschede, The Netherlands; Faculty of Health, Medicine and Life Sciences (FHML), School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands
| | - Jean H T Daemen
- Department of Surgery, Division of General Thoracic Surgery, Zuyderland Medical Center, Heerlen, The Netherlands; Faculty of Health, Medicine and Life Sciences (FHML), School for Oncology and Developmental Biology (GROW), Maastricht, The Netherlands
| | - Cornelis H Slump
- Faculty of Science and Technology (S&T), University of Twente, Enschede, The Netherlands
| | - Tom G J Loonen
- 3D Lab Radboudumc, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Yvonne L J Vissers
- Department of Surgery, Division of General Thoracic Surgery, Zuyderland Medical Center, Heerlen, The Netherlands
| | - Karel W E Hulsewé
- Department of Surgery, Division of General Thoracic Surgery, Zuyderland Medical Center, Heerlen, The Netherlands
| | - Erik R de Loos
- Department of Surgery, Division of General Thoracic Surgery, Zuyderland Medical Center, Heerlen, The Netherlands.
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20
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Zhang W, Nie B, Li HJ, Li Q, Li C, Wu YC. Inhibition of mild steel corrosion in 1 M HCl by chondroitin sulfate and its synergistic effect with sodium alginate. Carbohydr Polym 2021; 260:117842. [PMID: 33712176 DOI: 10.1016/j.carbpol.2021.117842] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 01/13/2023]
Abstract
The development of effective and environment-friendly corrosion inhibitors is of great significance for the protection of mild steel in hydrochloric acid media. Accordingly, a natural polysaccharide mixture inhibitor composed of chondroitin sulfate derived from pig cartilage (CS-PC) and sodium alginate (SA) is developed here, and the synergistic effect of the two polysaccharides towards adsorption on mild steel in 1 M HCl is studied. The inhibition performance has been studied using weight loss test, electrochemical investigations, SEM, SECM and UV methods. The results indicate that the mixtures of CS-PC and SA strongly inhibit the corrosion of mild steel compared to individual inhibitors (i.e., 95.18 % versus 72.78 %), and show a synergistic inhibition effect. The structure-activity relationship between the molecular structure of the CS-PC + SA mixture and its corrosion inhibition performance has been discussed by using the quantum chemistry calculation and molecular dynamics simulations. It is believed that these results have certain guiding significance for the rational design of efficient corrosion inhibitor.
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Affiliation(s)
- Weiwei Zhang
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China
| | - Boli Nie
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China
| | - Hui-Jing Li
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China; Weihai Chuanghui Environmental Protection Technology Co., Ltd., Weihai, 264200, PR China.
| | - Qinying Li
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China.
| | - Chaoyi Li
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China
| | - Yan-Chao Wu
- Weihai Marine Organism & Medical Technology Research Institute, Harbin Institute of Technology, Weihai, 264209, PR China; Weihai Chuanghui Environmental Protection Technology Co., Ltd., Weihai, 264200, PR China.
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Salajková Z, Holá M, Prochazka D, Ondráček J, Pavliňák D, Čelko L, Gregar F, Šperka P, Pořízka P, Kanický V, De Giacomo A, Kaiser J. Influence of sample surface topography on laser ablation process. Talanta 2021; 222:121512. [PMID: 33167223 DOI: 10.1016/j.talanta.2020.121512] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/31/2020] [Accepted: 08/03/2020] [Indexed: 11/22/2022]
Abstract
In this work we discuss how sample surface topography can significantly influence the laser ablation (LA) process and, in turn, the analytical response of the LA Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) method. Six different surface topographies were prepared on a certified aluminium alloy sample BAM 311 and SRM NIST 610 to investigate the phenomenon. All the samples were repetitively measured by LA-ICP-MS using a spot by spot analysis. The effect of laser fluence in the range of 1-13 J/cm2 was studied. For majority of measured isotopes, the ICP-MS signal was amplified with roughening of the sample surface. A stronger effect was observed on the Al alloy sample, where the more than sixty-time enhancement was achieved in comparison to the polished surface of the sample. Since the effect of surface topography is different for each analyte, it can be stated that surface properties affect not only the ICP-MS response, but also elemental fractionation in LA. The presented results show that different surface topographies may lead to misleading data interpretation because even when applying ablation preshots, the signal of individual elements changes. The utmost care must be taken when preparing the surface for single shot analysis or chemical mapping. On the other hand, by roughening the sample surface, it is possible to significantly increase the sensitivity of the method for individual analytes and supress a matrix effect.
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Bullen JC, Kenney JPL, Fearn S, Kafizas A, Skinner S, Weiss DJ. Improved accuracy in multicomponent surface complexation models using surface-sensitive analytical techniques: Adsorption of arsenic onto a TiO 2/Fe 2O 3 multifunctional sorbent. J Colloid Interface Sci 2020; 580:834-849. [PMID: 32731167 DOI: 10.1016/j.jcis.2020.06.119] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/17/2020] [Accepted: 06/28/2020] [Indexed: 11/17/2022]
Abstract
Novel composite materials are increasingly developed for water treatment applications with the aim of achieving multifunctional behaviour, e.g. combining adsorption with light-driven remediation. The application of surface complexation models (SCM) is important to understand how adsorption changes as a function of pH, ionic strength and the presence of competitor ions. Component additive (CA) models describe composite sorbents using a combination of single-phase reference materials. However, predictive adsorption modelling using the CA-SCM approach remains unreliable, due to challenges in the quantitative determination of surface composition. In this study, we test the hypothesis that characterisation of the outermost surface using low energy ion scattering (LEIS) improves CA-SCM accuracy. We consider the TiO2/Fe2O3 photocatalyst-sorbents that are increasingly investigated for arsenic remediation. Due to an iron oxide surface coating that was not captured by bulk analysis, LEIS significantly improves the accuracy of our component additive predictions for monolayer surface processes: adsorption of arsenic(V) and surface acidity. We also demonstrate non-component additivity in multilayer arsenic(III) adsorption, due to changes in surface morphology/porosity. Our results demonstrate how surface-sensitive analytical techniques will improve adsorption models for the next generation of composite sorbents.
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Affiliation(s)
- Jay C Bullen
- Department of Earth Science and Engineering, Faculty of Engineering, Imperial College London, London SW7 2BX, UK.
| | - Janice P L Kenney
- Department of Physical Sciences, MacEwan University, Edmonton, Alberta T5J 4S2P, Canada
| | - Sarah Fearn
- Department of Materials, Faculty of Engineering, Imperial College London, London SW7 2BX, UK
| | - Andreas Kafizas
- Department of Chemistry, White City Campus, Imperial College London, London W12 OBZ, UK; The Grantham Institute, Imperial College London, London, SW7 2AZ, UK
| | - Stephen Skinner
- Department of Materials, Faculty of Engineering, Imperial College London, London SW7 2BX, UK
| | - Dominik J Weiss
- Department of Earth Science and Engineering, Faculty of Engineering, Imperial College London, London SW7 2BX, UK; Civil and Environmental Engineering, E-Quad, Princeton University, Princeton, USA.
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Urupina D, Gaudion V, Romanias MN, Verriele M, Thevenet F. Method development and validation for the determination of sulfites and sulfates on the surface of mineral atmospheric samples using reverse-phase liquid chromatography. Talanta 2020; 219:121318. [PMID: 32887058 DOI: 10.1016/j.talanta.2020.121318] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 06/17/2020] [Accepted: 06/22/2020] [Indexed: 11/21/2022]
Abstract
Earlier studies suggest that SO2 gas reacts at the surface of mineral dust and forms sulfites or bisulfites, which are then converted to sulfates. In order to monitor and quantify the amounts of both sulfites and sulfates formed on the surface of mineral dusts of volcanic and desert origins an accurate and precise reversed-phase liquid chromatography method was developed and validated to extract, stabilize and individually analyze sulfites and sulfates initially present on the surface of dusts exposed to SO2. The method was developed on a 25 mm Restek Ultra Column C18, Particle size: 5 μm, I.D. 4.60 mm column which was dynamically coated with 1.0 mM cetylpyridinium chloride in 7% acetonitrile solution to produce a charged surface as recommended in the literature. Mobile phase used: 1 mM Potassium Hydrogen Phthalate at pH 6.5 at a flow rate of 1.0 ml/min with negative UV-Vis detection at 255 nm in 15 min. The method was validated for specificity, linearity and range, injection repeatability, stability, robustness, limit of detection and limit of quantitation, and sample preparation and extraction reproducibility. The method was adapted for straight sulfite and sulfate quantification: (i) of environmental samples, and (ii) natural samples additionally exposed to SO2 gas in a dedicated laboratory setup. The method was then successfully applied to quantify sulfites and sulfates on natural volcanic and a desert dust samples both collected in the environment and additionally exposed to SO2 gas in the laboratory. The method can be efficiently used to identify sulfites and sulfates on fresh volcanic ash following an eruption, on aeolian desert dust exposed to industrial pollutants, as well as for laboratory investigations of sulfite and sulfate formation on the surface of minerals and natural dusts of different origins.
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Min K, Guo P, Chen D, Huang S, Luo W, Ma M, Chen B, Yao S, Zuilhof H. Direct and quantitative in-situ analysis of third-hand smoke in and on various matrices by ambient desorption corona beam ionization mass spectrometry. Talanta 2020; 219:121330. [PMID: 32887064 DOI: 10.1016/j.talanta.2020.121330] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/18/2020] [Accepted: 06/23/2020] [Indexed: 12/21/2022]
Abstract
Third-hand smoke (THS) is composed of surface-deposited remnants resulting from tabacco-smoking. Because THS components have properties of remaining on, re-emitting from and reacting on and with surfaces, in-situ analysis of the components on different surfaces is both in high demand and challenging. The aim of this study is to establish desorption corona beam ionization (DCBI)-MS/MS as an analytical tool for THS research. To this end, an in-situ DCBI-MS/MS approach was developed for the quantitative analysis of typical THS environmental markers, i.e. nicotine and cotinine on different surfaces such as fruits, cotton clothing, glass, and toys etc. The limits of detection of nicotine and cotinine were both 1.4 μg m-2. Low-temperature DCBI-MS/MS was applied to the direct detection of THS on fingers without any skin damage. Smoking-related biomarkers analyses in urine were accomplished, with a 10 s DCBI analysis time. The on-surface tobacco-specific nitrosamines (TSNAs), such as 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal) (NNA), 4-(methylnitrosamino)-1-(3-pyridinyl)-1-butanone (NNK), and N-nitroso nornicotine (NNN) were in-situ successfully detected in dust samples.
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Affiliation(s)
- Ke Min
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China
| | - Ping Guo
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China
| | - Dongying Chen
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China
| | - Si Huang
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China; Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, 6703 WE, Wageningen, the Netherlands
| | - Wei Luo
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China; Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, 6703 WE, Wageningen, the Netherlands
| | - Ming Ma
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China
| | - Bo Chen
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China.
| | - Shouzhuo Yao
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China.
| | - Han Zuilhof
- Key Laboratory of Phytochemical R&D of Hunan Province, Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research of Ministry of Education, Hunan Normal University, Changsha, 410081, China; Laboratory of Organic Chemistry, Wageningen University, Stippeneng 4, 6703 WE, Wageningen, the Netherlands; Department of Chemical and Materials Engineering, Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia.
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Martinez MAF, Balderrama ÍDF, Karam PSBH, de Oliveira RC, de Oliveira FA, Grandini CR, Vicente FB, Stavropoulos A, Zangrando MSR, Sant'Ana ACP. Surface roughness of titanium disks influences the adhesion, proliferation and differentiation of osteogenic properties derived from human. Int J Implant Dent 2020; 6:46. [PMID: 32839885 PMCID: PMC7445212 DOI: 10.1186/s40729-020-00243-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 07/02/2020] [Indexed: 01/02/2023] Open
Abstract
PURPOSE The aim of this study was to investigate the response of osteogenic cell lineage and gingival fibroblastic cells to different surface treatments of grade IV commercially pure Titanium (cpTi) disks. MATERIAL AND METHODS Grade IV cpTi disks with different surfaces were produced: machined (M), sandblasting (B), sandblasting and acid subtraction (NP), and hydrophilic treatment (ACQ). Surface microtopography characteristics and chemical composition were investigated by scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS). Adhesion and proliferation of SC-EHAD (human surgically-created early healing alveolar defects) and HGF-1 (human gingival fibroblasts) on Ti disks were investigated at 24 and 48 h, and osteogenic differentiation and mineralization were evaluated by assessing alkaline phosphatase (ALP) activity and alizarin red staining, respectively. RESULTS No significant differences were found among the various surface treatments for all surface roughness parameters, except for skewness of the assessed profile (Rsk) favoring M (p = 0.035 ANOVA). M disks showed a slightly higher (p > 0.05; Kruskal-Wallis/Dunn) adhesion of HGF-1 (89.43 ± 9.13%) than SC-EHAD cells (57.11 ± 17.72%). ACQ showed a significantly higher percentage of SC-EHAD (100%) than HGF-1 (69.67 ± 13.97%) cells adhered at 24 h. SC-EHAD cells expressed increased ALP activity in osteogenic medium at M (213%) and NP (235.04%) surfaces, but higher mineralization activity on ACQ (54.94 ± 4.80%) at 14 days. CONCLUSION These findings suggest that surface treatment influences the chemical composition and the adhesion and differentiation of osteogenic cells in vitro. CLINICAL RELEVANCE Hydrophilic surface treatment of grade IV cpTi disks influences osteogenic cell adhesion and differentiation, which might enhance osseointegration.
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Affiliation(s)
- Maria Alejandra Frias Martinez
- Department of Prosthodontics and Periodontics, Discipline of Periodontics, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, 17012-901, Brazil
| | - Ísis de Fátima Balderrama
- Department of Prosthodontics and Periodontics, Discipline of Periodontics, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, 17012-901, Brazil.
- Department of Periodontology, Faculty of Odontology, Malmö University, Malmö, Sweden.
| | - Paula Stephania Brandão Hage Karam
- Department of Prosthodontics and Periodontics, Discipline of Periodontics, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, 17012-901, Brazil
| | | | - Flávia Amadeu de Oliveira
- Department of Biological Sciences, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, Brazil
| | | | - Fábio Bossoi Vicente
- Anelasticity and Biomaterials Laboratory, São Paulo State University, Bauru, SP, Brazil
| | - Andreas Stavropoulos
- Department of Periodontology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Mariana Schutzer Ragghianti Zangrando
- Department of Prosthodontics and Periodontics, Discipline of Periodontics, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, 17012-901, Brazil
| | - Adriana Campos Passanezi Sant'Ana
- Department of Prosthodontics and Periodontics, Discipline of Periodontics, School of Dentistry at Bauru, University of São Paulo, Bauru, SP, 17012-901, Brazil
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Bitencourt SB, Catanoze IA, da Silva EVF, Dos Santos PH, Dos Santos DM, Turcio KHL, Guiotti AM. Effect of acidic beverages on surface roughness and color stability of artificial teeth and acrylic resin. J Adv Prosthodont 2020; 12:55-60. [PMID: 32377317 PMCID: PMC7183855 DOI: 10.4047/jap.2020.12.2.55] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 03/04/2020] [Accepted: 03/12/2020] [Indexed: 12/12/2022] Open
Abstract
PURPOSE The aim was to evaluate the effect of four acidic beverages on the roughness (Ra) and color change (ΔEab) of two brands of artificial teeth and a heat-polymerized acrylic resin (HPAR) for use in a prosthetic base. MATERIALS AND METHODS All materials were divided into 5 groups, according to the used acidic beverage (artificial saliva - control, red wine, orange juice, coke-based, and lemon juice-based soft drink). The immersion process was divided into two stages: T1 - immersion in the acidic solutions for 10 minutes for 14 days; T2 - after T1, the samples were immersed in grape juice for 14 days. The Ra of the samples was evaluated in a rugosimeter and the ΔEab in a spectrophotometer, before and after the immersions. The analysis of variance of one (ΔEab) and two factors (Ra) and Tukey were performed (α=.05). RESULTS There was a statistical difference for roughness after immersion (T1) for Trilux and Tritone teeth, regardless of the acid solution. For Trilux teeth, all acid solutions increased Ra (P<.05). For Tritone teeth, only the coke-based soft drink did not statistically change Ra. Grape juice (T2) altered Ra only of artificial teeth (P<.05). The color was changed for all materials, after T1 and T2. CONCLUSION In general, the acidic solutions changed the Ra and ΔEab of HPAR and artificial teeth after T1. The grape juice altered the roughness only of the artificial teeth, promoting a clinically acceptable color change in the materials.
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Affiliation(s)
- Sandro Basso Bitencourt
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Isabela Araguê Catanoze
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Emily Vivianne Freitas da Silva
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Paulo Henrique Dos Santos
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Daniela Micheline Dos Santos
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Karina Helga Leal Turcio
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
| | - Aimée Maria Guiotti
- Department of Dental Materials and Prosthodontics, São Paulo State University (UNESP), School of Dentistry, São Paulo, Brazil
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Zhang W, Li HJ, Chen L, Zhang S, Ma Y, Ye C, Zhou Y, Pang B, Wu YC. Fructan from Polygonatum cyrtonema Hua as an eco-friendly corrosion inhibitor for mild steel in HCl media. Carbohydr Polym 2020; 238:116216. [PMID: 32299575 DOI: 10.1016/j.carbpol.2020.116216] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/24/2020] [Accepted: 03/24/2020] [Indexed: 11/17/2022]
Abstract
An effective and biodegradable polygonatum fructan (PF) from Polygonatum cyrtonema Hua was studied as an eco-friendly corrosion inhibitor for mild steel protection in 1 M HCl, whose inhibition performance was studied by weight loss tests, electrochemical techniques, and surface analysis techniques (SECM, FTIR). The experimental results showed that PF has outstanding inhibition performance for mild steel in hydrochloric acid, and the inhibition efficiency increased with the increase of its concentration and temperature. Polarization studies indicated that PF is a mixed-type corrosion inhibitor, and its adsorption mode conforms to Langmuir isotherm, mainly chemisorption. An adsorption-related protective inhibitor film formed on the surface of mild steel was verified and investigated based on its surface analysis and characterization. Quantum chemical analysis showed that the adsorption of PF on the surface of mild steel has obvious chemical properties.
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Affiliation(s)
- Weiwei Zhang
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Hui-Jing Li
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China.
| | - Liwei Chen
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Siyi Zhang
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Yongjian Ma
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Chen Ye
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Yuanqing Zhou
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Boyi Pang
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China
| | - Yan-Chao Wu
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, PR China; Weihai Institute of Marine Biomedical Industrial Technology, Wendeng District, Weihai 264400, PR China.
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Ajdnik U, Finšgar M, Fras Zemljič L. Characterization of chitosan-lysine surfactant bioactive coating on silicone substrate. Carbohydr Polym 2020; 232:115817. [PMID: 31952614 DOI: 10.1016/j.carbpol.2019.115817] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 12/23/2019] [Accepted: 12/30/2019] [Indexed: 12/22/2022]
Abstract
Chitosan (Chi) and anionic surfactant derived from lysine (77KS) were used to prepare a novel bioactive coating and as a drug delivery system for amoxicillin (AMOX) on a model polydimethylsiloxane (PDMS) surface. The bioactive coating was formulated as polyelectrolyte-surfactant complex (PESC). Aggregation behaviour between the cationic Chi and oppositely charged 77KS in bulk was analysed using turbidity and ζ-potential measurement. Furthermore, the adsorption and stability of the formulations were evaluated using quartz crystal microbalance with dissipation (QCM-D). The effect of the ionic strength and of the ultraviolet/ozone (UVO) activation of the PDMS films on the adsorption behaviour of the PESC complex was also examined. QCM-D monitoring showed stable adsorption of bare and AMOX-loaded complex on non-activated PDMS films, while the coating on UVO-activated PDMS samples desorbed after the rinsing step. Finally, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry confirmed successful and homogenously distributed compounds.
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Affiliation(s)
- Urban Ajdnik
- University of Maribor, Faculty of Mechanical Engineering, Institute for Engineering Materials and Design, Smetanova ulica 17, 2000 Maribor, Slovenia.
| | - Matjaž Finšgar
- University of Maribor, Faculty of Chemistry and Chemical Engineering, Smetanova ulica 17, 2000 Maribor, Slovenia.
| | - Lidija Fras Zemljič
- University of Maribor, Faculty of Mechanical Engineering, Institute for Engineering Materials and Design, Smetanova ulica 17, 2000 Maribor, Slovenia.
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Feng Y, Feng L, Wang Z, Zhang X. Surface analysis of 4-(bis(5-bromo-1H-indol-3-yl)methyl)phenol adsorbed on copper by spectroscopic experiments. Spectrochim Acta A Mol Biomol Spectrosc 2020; 228:117752. [PMID: 31711718 DOI: 10.1016/j.saa.2019.117752] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/01/2019] [Accepted: 11/02/2019] [Indexed: 06/10/2023]
Abstract
The new compound of 4-(bis(5-bromo-1H-indol-3-yl)methyl)phenol (BMP) is synthesized through a one-step reaction. Then the inhibition mechanism of inhibitor on copper surface is investigated by Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Moreover, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) is employed to characterize the surface morphology of studied copper and electrochemical impendence spectroscopy (EIS) is carried out to study the inhibition efficiency of the inhibitor. From these results obtained, it can be concluded that BMP is considered as corrosion inhibitor for copper in sulfuric solution.
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Affiliation(s)
- Yangyang Feng
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Li Feng
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China
| | - Zhenqiang Wang
- Chongqing Key Laboratory of Green Synthesis and Applications, College of Chemistry, Chongqing Normal University, Chongqing 401331, China.
| | - Xiaohui Zhang
- College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044, China.
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Park SJ, Gupta KC, Kim H, Kim S, Kang IK. Osteoblast behaviours on nanorod hydroxyapatite-grafted glass surfaces. Biomater Res 2019; 23:28. [PMID: 31890270 PMCID: PMC6925421 DOI: 10.1186/s40824-019-0178-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 12/03/2019] [Indexed: 11/10/2022] Open
Abstract
Background The goal of this study is to obtain basic information to improve the bone adhesion of silica components, which are used as the main ingredient in glass ionomer cement (GIC). To achieve this, nanorod hydroxyapatite (nHA) was grafted to the surface of silica cover glass. Surface analysis confirmed nHA was joined to the glass surface and biocompatibility with osteoblasts was investigated. Results The grafting of nHA on the surface of slide cover glass (Glass) was confirmed by X-ray photoelectron spectroscopy (XPS) and contact angle (θ) measurement. MC3T3-E1 cells were more stretched out on the nHA-grafted cover glass (Glass-nHA) in comparison to the Glass. In addition, the Glass-nHA was more bioactive in supporting the proliferation of MC3T3-E1 cells in comparison to cells seeded on the Glass. Conclusion The Glass-nHA was to be highly bioactive and this might be useful information for property modification of GIC.
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Affiliation(s)
- So Jung Park
- 1Department of Polymer Science and Engineering, Kyungpook National University, Daegu, 702-701 South Korea
| | - Kailash Chandra Gupta
- 1Department of Polymer Science and Engineering, Kyungpook National University, Daegu, 702-701 South Korea.,Department of Chemistry, Polymer Research Laboratory, I. I. T. Roorkee, Roorkee, 247 667 India
| | - Hun Kim
- Jeil Medical Corporation, Seoul, 08378 South Korea
| | - Sukyoung Kim
- 4School of Materials Science and Engineering, Yeungnam University, Gyeongbuk, 712-749 South Korea
| | - Inn-Kyu Kang
- 1Department of Polymer Science and Engineering, Kyungpook National University, Daegu, 702-701 South Korea
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31
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Sugimura N, Watabe Y, Shibue T. Triboionization: a Novel Ionization Method by Peeling of Cohesive Substances for Mass Spectrometry. J Am Soc Mass Spectrom 2019; 30:1503-1511. [PMID: 31102188 DOI: 10.1007/s13361-019-02220-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/06/2019] [Accepted: 04/06/2019] [Indexed: 06/09/2023]
Abstract
A novel ionization/sampling method termed triboionization was developed. Triboionization is an ionization method that only uses cohesive substances, such as food wrap or sticky tape, and does not require an electrode, electric power supply, heat source, light source, radiation, or gas, unlike most other conventional ambient ionization methods. In this study, the sample compound attached to adhesive tape or plastic wrap was quickly peeled off at a distance of approximately 2 cm from the atmospheric interface of a mass spectrometer. All of the five types of food wrap and 13 types of adhesive tape tested successfully ionized caffeine. Nine out of ten model compounds were detected as the corresponding molecular ions in the positive or negative mode by this ionizing contrivance using an oriented polypropylene adhesive tape. The detected molecular ions were typically protonated molecules or sodium adducts in the positive mode or deprotonated molecules in the negative mode. The elemental compositions of the observed ions were confirmed within 5 ppm by high-resolution mass spectrometry. The triboionization phenomenon was considered to depend on physical and electronic events caused by peeling off a cohesive substance. Triboionization is able to provide a compact ion source using only mechanical mechanisms. Additionally, triboionization allows sticky tape to be used as a convenient sampling device for surface analysis.
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Affiliation(s)
- Natsuhiko Sugimura
- Materials Characterization Central Laboratory, Waseda University, 3-4-1 Ohkubo, Shinjyuku, Tokyo, 169-8555, Japan.
| | - Yuki Watabe
- Materials Characterization Central Laboratory, Waseda University, 3-4-1 Ohkubo, Shinjyuku, Tokyo, 169-8555, Japan
| | - Toshimichi Shibue
- Materials Characterization Central Laboratory, Waseda University, 3-4-1 Ohkubo, Shinjyuku, Tokyo, 169-8555, Japan
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Zheng K, Li H, Xu L, Li S, Wang L, Wen X, Liu Q. The influence of humic acids on the weathering of pyrite: Electrochemical mechanism and environmental implications. Environ Pollut 2019; 251:738-745. [PMID: 31112928 DOI: 10.1016/j.envpol.2019.05.060] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 03/11/2019] [Accepted: 05/12/2019] [Indexed: 06/09/2023]
Abstract
Pyrite weathering often occurs in nature and causes heavy metal ion pollution and acid mine drainage during the process. Humic acid (HA) is a critical natural organic material that can bind metal ions, thus affecting metal transfer and transformation. In this work, in situ electrochemical techniques combined with spectroscopic analysis were adopted to investigate the interfacial processes involved in pyrite weathering with/without HA. The results showed that the pyrite weathering mechanism with/without HA is FeS2 → Fe2+ + 2S0 + 2e-. The presence of HA did not change the pyrite weathering mechanism, but HA adsorbs on the pyrite surface and inhibits the further transformation of sulfur. Furthermore, HA and Fe(II) ions can form complex at 45.0 °C. Increased concentration of HA, decreased HA solution acidity or decreased environmental temperature would all weaken the pyrite weathering, for the above conditions cause pyrite weathering to have a larger resistance of the double layer and a larger passive film resistance. Pyrite will release 73.7 g m-2·y-1 Fe2+ to solution at pH 4.5, and the amount decreases to 36.8 g m-2·y-1 in the presence of 100 mg/L HA. This study provides an in situ electrochemical method for the assessment of pyrite weathering.
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Affiliation(s)
- Kai Zheng
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100039, China
| | - Heping Li
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China.
| | - Liping Xu
- Zhejiang Pharmaceutical College, Ningbo, 221116, China
| | - Shengbin Li
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Luying Wang
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Xiaoying Wen
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China
| | - Qingyou Liu
- Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, 550081, China; University of Chinese Academy of Sciences, Beijing, 100039, China.
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Gogoi H, Leiviskä T, Rämö J, Tanskanen J. Production of aminated peat from branched polyethylenimine and glycidyltrimethylammonium chloride for sulphate removal from mining water. Environ Res 2019; 175:323-334. [PMID: 31150931 DOI: 10.1016/j.envres.2019.05.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 06/09/2023]
Abstract
A novel bio-based anion exchanger was developed to remove sulphate from synthetic solutions and mine water. Different modification parameters such as chemical dosage and reaction time were tested when using a unique combination of branched polyethylenimine (PEI) and glycidyltrimethylammonium chloride (GTMAC) to produce an aminated biosorbent (termed PG-Peat). The novel and environment-friendly modification method was shown by FTIR and XPS analyses to be able to introduce quaternary ammonium and N-H groups into PG-Peat. The optimal modification conditions (PEI: 0.26 mmol/g, GTMAC: 0.0447 mol/g, reaction time: 18 h) resulted in the maximum sulphate uptake capacity (189.5 ± 2.7 mg/g) with a partition coefficient value of 0.02 mg/g/μM under acidic conditions. At low pH, amine groups on the peat surface became cationized, thereby resulting in a higher sulphate removal capacity. Batch sorption tests using PG-Peat exhibited rapid sulphate sorption after only five minutes of contact. The sulphate uptake by PG-Peat was unaffected by the presence of varying chloride concentrations, while slightly lower uptake capacity was observed when different concentrations of nitrate were present. The biosorbent showed high recyclability, which was revealed in regeneration studies. Tests were performed involving real mine water, where PG-Peat showed its potential to be a highly efficient biosorbent for sulphate removal at low pH values, indicating its suitability for treating acidic mine waters.
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Affiliation(s)
- Harshita Gogoi
- Chemical Process Engineering, P.O. Box 4300, FIN-90014, University of Oulu, Oulu, Finland.
| | - Tiina Leiviskä
- Chemical Process Engineering, P.O. Box 4300, FIN-90014, University of Oulu, Oulu, Finland
| | - Jaakko Rämö
- Chemical Process Engineering, P.O. Box 4300, FIN-90014, University of Oulu, Oulu, Finland
| | - Juha Tanskanen
- Chemical Process Engineering, P.O. Box 4300, FIN-90014, University of Oulu, Oulu, Finland
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Kashani FZ, Ghoreishi SM, Khoobi A. Experimental and statistical analysis on a nanostructured sensor for determination of p-hydroxybenzoic acid in cosmetics. Mater Sci Eng C Mater Biol Appl 2019; 94:45-55. [PMID: 30423729 DOI: 10.1016/j.msec.2018.08.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 08/03/2018] [Accepted: 08/31/2018] [Indexed: 01/01/2023]
Abstract
In this research, differential pulse voltammetry (DPV) coupled with experimental design, was used for determination of p-hydroxybenzoic acid (PHB) in cosmetics. Optimization of effecting parameters was carried out based on rotatable central composite design (RCCD) and response surface methodology (RSM) at the surface of a nanostructured electrode for achieving the best sensitivity. Sol-gel process was used for synthesize of nickel titanate (NiTiO3) nanoceramics. The structural and morphological characterization of the nanoparticles was studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Then the NiTiO3 nanopowders were used for surface modification of a carbon paste modified electrode (CPE). Surface characterization of the electrode was accomplished using SEM, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Under the optimized conditions, the voltammograms exhibited two linear dynamic ranges of 0.7-80.0 μM and 80.0-1000.0 μM for PHB with the detection limit of 62.0 nM (S/N = 3). Finally the NiTiO3 nanoceramics modified carbon paste electrode (NiTiO3/CPE) could be employed for the determination of PHB in real samples with satisfactory results.
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Affiliation(s)
- Fahimeh Zeraatkar Kashani
- Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box. 87317-51167, Islamic Republic of Iran
| | - Sayed Mehdi Ghoreishi
- Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box. 87317-51167, Islamic Republic of Iran.
| | - Asma Khoobi
- Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, P.O. Box. 87317-51167, Islamic Republic of Iran
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Jebadurai SG, Raj RE, Sreenivasan VS, Binoj JS. Comprehensive characterization of natural cellulosic fiber from Coccinia grandis stem. Carbohydr Polym 2019; 207:675-83. [PMID: 30600052 DOI: 10.1016/j.carbpol.2018.12.027] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 11/21/2018] [Accepted: 12/10/2018] [Indexed: 11/24/2022]
Abstract
The anatomical, physico-chemical, mechanical, thermal and surface characteristics of Coccinia grandis fiber (CGF) were studied for a potential substitute to the harmful synthetic fibers. The anatomical analysis of Coccinia grandis stem reveals the presence of high strength xylem fibers. Polarized light microscopy and scanning electron microscopy of CGF shows a hierarchical cell structure composed of a primary and a secondary cell wall, cell lumen and the middle lamellae. The average cross-sectional area and density of the CGF were 0.0111 mm2 and 1.5175 ± 0.005 g/cm3 respectively. The x-ray diffraction and Fourier transform infrared analyses of the fiber indicates the presence of cellulose Iβ with a crystallinity index of 46.09%. The mean Young's modulus and tensile strength of the CGF were 124 GPa and 775 MPa respectively, which is sufficient enough for the reinforcement in polymer composites. The thermogravimetric analysis confirms the thermal stability of CGF up to 250 °C, which is well within the polymerization process temperature.
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Kovač J, Finšgar M. Analysis of the Thermal Stability of Very Thin Surface Layers of Corrosion Inhibitors by Time-of-Flight Secondary Ion Mass Spectrometry. J Am Soc Mass Spectrom 2018; 29:2305-2316. [PMID: 30120717 DOI: 10.1007/s13361-018-2048-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 08/02/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
The powerful nature of the secondary ion mass spectrometry (SIMS) technique was explored in order to analyse very thin surface layers that were self-assembled on steel material from acidic solution. These surface layers are adsorbed corrosion inhibitors. The SIMS technique proved useful to characterise the molecular structure and homogeneity of thin surface layers in the nanometre range of specific analytes on the metallic substrate. Using SIMS, the thermal stability of these layers was further investigated and the desorption energy at a certain temperature was determined, where special attention was devoted to the method's static limit. In order to compare, and for certain cases emphasise, the benefits gained by using SIMS in such surface analysis compared with the X-ray photoelectron spectroscopy (XPS) method, the same samples were also analysed by means of the latter. XPS is usually considered to be the most powerful analytical tool in surface analysis studies, but, as shown herein, it has certain limitations compared to SIMS. Finally, the surface topography was investigated by employing atomic force microscopy (AFM) in order to carry out a comprehensive surface analysis. Graphical Abstract ᅟ.
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Affiliation(s)
- Janez Kovač
- Department of Surface Engineering and Optoelectronics, Jozef Stefan Institute, Jamova 39, 1000, Ljubljana, Slovenia
| | - Matjaž Finšgar
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, 2000, Maribor, Slovenia.
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Robinson N, Robertson C, Gladden LF, Jenkins SJ, D'Agostino C. Direct Correlation between Adsorption Energetics and Nuclear Spin Relaxation in a Liquid-saturated Catalyst Material. Chemphyschem 2018; 19:2472-2479. [PMID: 29923663 DOI: 10.1002/cphc.201800513] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Indexed: 11/09/2022]
Abstract
The ratio of NMR relaxation time constants <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>T</mml:mi> <mml:mn>1</mml:mn></mml:msub> <mml:mo>/</mml:mo> <mml:msub><mml:mi>T</mml:mi> <mml:mn>2</mml:mn></mml:msub> </mml:mrow> </mml:math> provides a non-destructive indication of the relative surface affinities exhibited by adsorbates within liquid-saturated mesoporous catalysts. In the present work we provide supporting evidence for the existence of a quantitative relationship between such measurements and adsorption energetics. As a prototypical example with relevance to green chemical processes we examine and contrast the relaxation characteristics of primary alcohols and cyclohexane within an industrial silica catalyst support. <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow><mml:msub><mml:mi>T</mml:mi> <mml:mn>1</mml:mn></mml:msub> <mml:mo>/</mml:mo> <mml:msub><mml:mi>T</mml:mi> <mml:mn>2</mml:mn></mml:msub> </mml:mrow> </mml:math> values obtained at intermediate magnetic field strength are in good agreement with DFT adsorption energy calculations performed on single molecules interacting with an idealised silica surface. Our results demonstrate the remarkable ability of this metric to quantify surface affinities within systems of relevance to liquid-phase heterogeneous catalysis, and highlight NMR relaxation as a powerful method for the determination of adsorption phenomena within mesoporous solids.
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Affiliation(s)
- Neil Robinson
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, United Kingdom.,Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Christopher Robertson
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, United Kingdom
| | - Lynn F Gladden
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, United Kingdom
| | - Stephen J Jenkins
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom
| | - Carmine D'Agostino
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, United Kingdom.,Present address: School of Chemical Engineering and Analytical Science, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
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Khan MA, Bian P, Qu J, Chen H, Liu H, Foley M, Yao Y, Ringer SP, Zheng R. Non-destructive analysis on nano-textured surface of the vertical LED for light enhancement. Ultramicroscopy 2018; 196:1-9. [PMID: 30267990 DOI: 10.1016/j.ultramic.2018.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 07/10/2018] [Accepted: 09/12/2018] [Indexed: 10/28/2022]
Abstract
In this work, the nano-textured surface of a GaN-based vertical light emitting diode (VLED) is characterized using a unified framework of non-destructive techniques (NDT) incorporating scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy, Photoluminescence (PL), and X-ray diffraction (XRD) to optimize the light output efficiency. The surface roughness of ∼300 nm is revealed by AFM. Compressive stress-state of 0.667 GPa in the GaN surface is indicated by the E2(high) and A1(LO) phonon peak values at 569 cm-1 and 736 cm-1, respectively, in Raman spectrum and the wavelength at 442 nm rather 450 nm in PL spectrum. Without damaging the LED, surface analysis by NDT helps to advance the understanding of the optimized angular light redistribution subject to the high-roughness surface and the negative impacts of the stress induced at the top GaN layer, which leads to the optical efficiency degradation of the VLED. Furthermore, the impact of texturing on underneath n-GaN and MQWs layers is investigated via SEM-based transmission Kikuchi diffraction (TKD) and aberration-corrected scanning transmission electron microscopy (AC-STEM) and revealed a smooth surface morphology and good crystalline quality, indicating that the etch-induced damage by texture engineering does not impair the active region of the VLED. Accordingly, prospective optimizations are suggested in the context of surface engineering for light enhancement in VLEDs.
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Affiliation(s)
- Mansoor Ali Khan
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Pengju Bian
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Jiangtao Qu
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Hansheng Chen
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Hongwei Liu
- Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Matthew Foley
- Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia
| | - Yin Yao
- Electron Microscope Unit, University of New South Wales, Sydney, NSW 2052, Australia
| | - S P Ringer
- School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW 2006, Australia
| | - Rongkun Zheng
- School of Physics, The University of Sydney, Sydney, NSW 2006, Australia; The University of Sydney Nano Institute, The University of Sydney, Sydney, NSW 2006, Australia; Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, NSW 2006, Australia.
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Pandiyaraj KN, Ramkumar MC, Arun Kumar A, Padmanabhan PVA, Pichumani M, Bendavid A, Cools P, De Geyter N, Morent R, Kumar V, Gopinath P, Su PG, Deshmukh RR. Evaluation of surface properties of low density polyethylene (LDPE) films tailored by atmospheric pressure non-thermal plasma (APNTP) assisted co-polymerization and immobilization of chitosan for improvement of antifouling properties. Mater Sci Eng C Mater Biol Appl 2018; 94:150-160. [PMID: 30423696 DOI: 10.1016/j.msec.2018.08.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 06/25/2018] [Accepted: 08/30/2018] [Indexed: 11/26/2022]
Abstract
This work describes the development of antifouling functional coatings on the surface of low density polyethylene (LDPE) films by means of atmospheric pressure non-thermal plasma (APNTP) assisted copolymerization using a mixture of acrylic acid and poly (ethylene glycol). The aim of the study was to investigate the antifouling properties of the plasma copolymerized LDPE films and the same was carried out as a function of deposition time with fixed applied potential of 14 kV. In a second stage, the plasma copolymerized LDPE films were functionalized with chitosan (CHT) to further enhance its antifouling properties. The surface hydrophilicity, structural, topographical and chemistry of the plasma copolymerized LDPE films were examined by contact angle (CA), X-ray diffraction (XRD), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Coating stability was also studied in detail over a storage time of 15 days by storing in water and air. The antifouling properties of the plasma copolymerized LDPE films were examined via protein adsorption and platelet adhesion studies. CA study showed significant changes in surface wettability after the coating process. XPS and FTIR analysis proved the presence of a dense multifunctional coating and an efficient immobilization of CHT. Substantial amendments in surface topography were observed, positively enhancing the overall surface hydrophilicity. Finally, in-vitro analysis showed excellent antifouling behavior of the surface modified LDPE films.
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Affiliation(s)
- K N Pandiyaraj
- Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, Coimbatore 641062, India.
| | - M C Ramkumar
- Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, Coimbatore 641062, India
| | - A Arun Kumar
- Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, Coimbatore 641062, India
| | - P V A Padmanabhan
- Surface Engineering Laboratory, Department of Physics, Sri Shakthi Institute of Engineering and Technology, Coimbatore 641062, India
| | - M Pichumani
- Department of Nano Science and Technology, Sri Ramakrishna Engineering College, Coimbatore 641022, India
| | - Avi Bendavid
- Plasma Processing & Deposition Team, CSIRO Manufacturing Flagship, Australia
| | - Pieter Cools
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent, Belgium
| | - N De Geyter
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent, Belgium
| | - R Morent
- Research Unit Plasma Technology (RUPT), Department of Applied Physics, Faculty of Engineering, Ghent University, Jozef Plateaustraat 22, 9000 Ghent, Belgium
| | - Vinay Kumar
- Nanobiotechnology Laboratory, Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - P Gopinath
- Nanobiotechnology Laboratory, Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - Pi-Guey Su
- Department of Chemistry, Chinese Culture University, Taipei 111, Taiwan
| | - R R Deshmukh
- Department of Physics, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
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Girelli CMA, Vieira MA, Singh K, Cunha AG, Freitas JCC, Emmerich FG. Recovery of latent fingermarks from brass cartridge cases: Evaluation of developers, analysis of surfaces and internal ballistic effects. Forensic Sci Int 2018; 290:258-278. [PMID: 30099346 DOI: 10.1016/j.forsciint.2018.07.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 06/17/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
A study was undertaken wherein different fingermark developers were evaluated for the recovery of fingermarks from brass cartridge cases, besides the evaluation of factors such as firing effects and surface characterization of the cases. The latent fingermarks on α-brass plates, fired and unfired cartridge cases were deposited and aged for 1-14days before development with different developers. In order to mimic the fired cartridge case conditions, the brass plates were heated and examined at room temperature (RT), at 63 and at 200°C. The sequential treatment with cyanoacrylate, gun blue and fluorescent dye has been found to be the best among other developers for the recovery of latent fingermarks on brass surfaces including fired and unfired cartridge cases. Cartridge cases and other brass surfaces were also analyzed by surface characterization methods, including X-ray diffraction, scanning electronic microscopy, energy dispersive X-ray spectroscopy and metallographic examination. The tested surfaces correspond to α-phase brass Cu0.7Zn0.3 composition and have shown different surface morphologies (such as grain structure) and different levels of oxidation, even for cartridge cases obtained from the same batch. Due to this, the effectiveness of a given reagent for a specific brass surface is uncertain. Therefore, the application of the entire tested sequence of developers is strongly recommended. Further, the effects of firing on fingermarks on cartridge cases were examined, and the results indicated that the blowback of hot gases through the looseness between cartridge case and chamber wall of the firearm is the main cause responsible for deterioration of fingermarks during firing. Despite the recognized damage caused to fingermarks by the firing effects, good quality fingermarks were recovered from fired cartridge cases in which full fingermarks were intentionally deposited prior to firing. This indicates that the handling of the cartridges before and during the loading of the gun may have a strong influence on the quantity and quality of fingermarks, and that the firing itself is not the main responsible factor for the absence or low quality of fingermarks, as frequently reported in fired cartridge cases studies.
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Affiliation(s)
- Carlos M A Girelli
- Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espirito Santo, 29075-910 Vitoria-ES, Brazil; Identification Group, Federal Police of Brazil, 29114-670 Vila Velha-ES, Brazil.
| | - Mariana A Vieira
- Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espirito Santo, 29075-910 Vitoria-ES, Brazil
| | - Kulvir Singh
- Department of Forensic Science, Punjabi University, 147002 Patiala, India
| | - Alfredo G Cunha
- Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espirito Santo, 29075-910 Vitoria-ES, Brazil
| | - Jair C C Freitas
- Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espirito Santo, 29075-910 Vitoria-ES, Brazil
| | - Francisco G Emmerich
- Laboratory of Carbon and Ceramic Materials, Department of Physics, Federal University of Espirito Santo, 29075-910 Vitoria-ES, Brazil
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Finšgar M, Ristić T, Fardim P, Zemljič LF. Time-of-flight secondary ion mass spectrometry analysis of chitosan-treated viscose fibres. Anal Biochem 2018; 557:131-141. [PMID: 30053399 DOI: 10.1016/j.ab.2018.07.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 07/19/2018] [Accepted: 07/23/2018] [Indexed: 12/15/2022]
Abstract
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was employed to analyse cellulose viscose fibres treated with different chitosan-based solutions. The analysis reports several new features in the TOF-SIMS spectra for systems with various forms of chitosan-treated surfaces. The characteristic positive ion TOF-SIMS signals for chitosan are reported at m/z 147.90, 207.07, and 221.09, and characteristic signals for trimethyl chitosan are present at m/z 58.03 and 102.09. Furthermore, new fragments were suggested to characterise acetylated chitosan molecules. The relative surface concentrations of different species were obtained based on the specific signal ratios (originating from a specific fragment and cellulose). SIMS imaging was then performed in order to investigate the surface distribution of chitosan, trimethyl chitosan, and Na-containing nanoparticles. In order to perform TOF-SIMS imaging, the above-mentioned characteristic signals were employed and m/z 22.99 was used for Na nanoparticles.
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Affiliation(s)
- Matjaž Finšgar
- University of Maribor, Faculty of Chemistry and Chemical Engineering, Smetanova ulica 17, 2000, Maribor, Slovenia.
| | - Tijana Ristić
- Health Care Department, Tosama d.o.o., Production of Medical Supplies, Vir, Šaranovičeva cesta 35, 1230, Domžale, Slovenia
| | - Pedro Fardim
- Laboratory of Fibre and Cellulose, Åbo Akademi University, 20500, Turku, Finland
| | - Lidija Fras Zemljič
- University of Maribor, Faculty of Mechanical Engineering, SI-2000, Maribor, Smetanova Ulica 17, Slovenia.
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Galvão ES, Santos JM, Lima AT, Reis NC, Orlando MTD, Stuetz RM. Trends in analytical techniques applied to particulate matter characterization: A critical review of fundaments and applications. Chemosphere 2018; 199:546-568. [PMID: 29455125 DOI: 10.1016/j.chemosphere.2018.02.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 01/31/2018] [Accepted: 02/06/2018] [Indexed: 05/11/2023]
Abstract
Epidemiological studies have shown the association of airborne particulate matter (PM) size and chemical composition with health problems affecting the cardiorespiratory and central nervous systems. PM also act as cloud condensation nuclei (CNN) or ice nuclei (IN), taking part in the clouds formation process, and therefore can impact the climate. There are several works using different analytical techniques in PM chemical and physical characterization to supply information to source apportionment models that help environmental agencies to assess damages accountability. Despite the numerous analytical techniques described in the literature available for PM characterization, laboratories are normally limited to the in-house available techniques, which raises the question if a given technique is suitable for the purpose of a specific experimental work. The aim of this work consists of summarizing the main available technologies for PM characterization, serving as a guide for readers to find the most appropriate technique(s) for their investigation. Elemental analysis techniques like atomic spectrometry based and X-ray based techniques, organic and carbonaceous techniques and surface analysis techniques are discussed, illustrating their main features as well as their advantages and drawbacks. We also discuss the trends in analytical techniques used over the last two decades. The choice among all techniques is a function of a number of parameters such as: the relevant particles physical properties, sampling and measuring time, access to available facilities and the costs associated to equipment acquisition, among other considerations. An analytical guide map is presented as a guideline for choosing the most appropriated technique for a given analytical information required.
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Affiliation(s)
- Elson Silva Galvão
- Departamento de Engenharia Ambiental, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
| | - Jane Meri Santos
- Departamento de Engenharia Ambiental, Universidade Federal do Espírito Santo, Vitória, ES, Brazil
| | - Ana Teresa Lima
- Departamento de Engenharia Ambiental, Universidade Federal do Espírito Santo, Vitória, ES, Brazil
| | - Neyval Costa Reis
- Departamento de Engenharia Ambiental, Universidade Federal do Espírito Santo, Vitória, ES, Brazil
| | | | - Richard Michael Stuetz
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, NSW, Australia
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Kaur L, Singh K, Paul S, Singh S, Singh S, Jain SK. A Mechanistic Study to Determine the Structural Similarities Between Artificial Membrane Strat-M™ and Biological Membranes and Its Application to Carry Out Skin Permeation Study of Amphotericin B Nanoformulations. AAPS PharmSciTech 2018; 19:1606-1624. [PMID: 29488196 DOI: 10.1208/s12249-018-0959-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 01/15/2018] [Indexed: 11/30/2022] Open
Abstract
Type of biological membrane used in skin permeation experiment significantly affects skin permeation and deposition potential of tested formulations. In this study, a comparative study has been carried out to evaluate the potential of a synthetic membrane (Strat-M™) with rat, human, and porcine ear skin to carry out skin permeation study of nanoformulations of a high molecular weight drug, amphotericin B. Results demonstrated that the permeation of this high molecular weight drug through Strat-M™ showed close similitude to human skin. Value of correlation coefficient (R2) of log diffusion between Strat-M™ and human skin was found to be 0.99 which demonstrated the similarities of Strat-M™ membrane to the human skin. In similarity factor analysis, the value of f2 was also found to be 85, which further demonstrated the similarities of Strat-M™ membrane to human skin. Moreover, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis of synthetic and biological membranes depicted almost similar morphological features (thickness, pore size, surface morphology, and diameter) of synthetic membrane with human skin. The results of the study demonstrated Strat-M™ as a better alternative to carry out skin permeation experiment due to the consistent results, reproducibility, easy availability, and minimum variability with human skin.
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Wan KY, Wong KW, Chow AHL, Chow SF. Impact of molecular rearrangement of amphiphilic stabilizers on physical stability of itraconazole nanoparticles prepared by flash nanoprecipitation. Int J Pharm 2018; 542:221-231. [PMID: 29555440 DOI: 10.1016/j.ijpharm.2018.03.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 02/08/2018] [Accepted: 03/06/2018] [Indexed: 11/16/2022]
Abstract
Flash nanoprecipitation (FNP) is a controlled antisolvent precipitation process that has proven effective for consistent production of drug nanoparticles with a defined mean particle size and narrow particle size distribution. However, physical instability of the generated nanoparticles remains a major challenge in the application of this technology in pharmaceutical formulation. Aimed at resolving this problem, the present study has investigated the FNP process and associated stabilization mechanism of itraconazole (ITZ) nanoparticles through in-depth nanoparticle characterization. Results showed that ITZ nanoparticles could be reproducibly produced with a mean particle size <100 nm and a polydispersity index <0.2 in the presence of amphiphilic stabilizers (ASs). Surface analysis of freshly formed nanoparticles by X-ray photoelectron spectroscopy (XPS) revealed initially a disordered packing structure and subsequently a time-dependent molecular rearrangement of incorporated AS towards a micelle-like structure. The faster the molecular rearrangement of AS, the more stable the nanoparticles, as monitored by the change in particle size with time. These findings may have important implications for the selection of effective ASs for formulating stable drug nanoparticles. The present study is the first of its kind to demonstrate the utility of XPS to track the molecular transport of stabilizers in rapidly generated nanoparticles.
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Affiliation(s)
- Ka Yee Wan
- School of Pharmacy, The Chinese University of Hong Kong, Sha Tin, Hong Kong
| | - Ka Wai Wong
- HL Science & Technology Limited, Kowloon, Hong Kong
| | - Albert Hee Lum Chow
- School of Pharmacy, The Chinese University of Hong Kong, Sha Tin, Hong Kong.
| | - Shing Fung Chow
- Department of Pharmacology and Pharmacy, The University of Hong Kong, Pokfulam, Hong Kong.
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45
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Finšgar M. Surface analysis of 2-mercapto-1-methylimidazole adsorbed on copper by X-ray photoelectron spectroscopy. Spectrochim Acta A Mol Biomol Spectrosc 2018; 190:290-297. [PMID: 28941413 DOI: 10.1016/j.saa.2017.09.048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/10/2017] [Accepted: 09/16/2017] [Indexed: 06/07/2023]
Abstract
A detailed analysis using X-ray photoelectron spectroscopy (XPS) is presented for the system of 2-mercapto-1-methylimidazole (MMeI) adsorbed on Cu in 3wt% NaCl solution. High-resolution and survey XPS spectra and XPS-excited Auger L3M4,5M4,5 spectra were analysed in detail. Surface analysis revealed that the MMeI molecules do not lie flat on the surface via π-d interactions, but adsorb on the surface through an N-S-bridge configuration. Moreover, the characteristic Cu(I)-MMeI connection fingerprint, which is usually observed for these kinds of molecules, was not observed. Tougaard thickness analysis showed that a relatively thin MMeI surface layer (0.3-0.6nm) is formed on the Cu substrate after 1h of immersion. Herein, MMeI is considered as a Cu corrosion inhibitor for chloride solution for short-term immersion periods. Based on the XPS analysis, an explanation of why MMeI is not effective for longer-term immersion periods, compared with similar compounds, is given.
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Affiliation(s)
- Matjaž Finšgar
- University of Maribor, Faculty of Chemistry and Chemical Engineering, Smetanova ulica 17, 2000 Maribor, Slovenia.
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Ramírez-Aldaba H, Vazquez-Arenas J, Sosa-Rodríguez FS, Valdez-Pérez D, Ruiz-Baca E, García-Meza JV, Trejo-Córdova G, Lara RH. Assessment of biofilm changes and concentration-depth profiles during arsenopyrite oxidation by Acidithiobacillus thiooxidans. Environ Sci Pollut Res Int 2017; 24:20082-20092. [PMID: 28702905 DOI: 10.1007/s11356-017-9619-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Biofilm formation and evolution are key factors to consider to better understand the kinetics of arsenopyrite biooxidation. Chemical and surface analyses were carried out using Raman spectroscopy, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), glow discharge spectroscopy (GDS), and protein analysis (i.e., quantification) in order to evaluate the formation of intermediate secondary compounds and any significant changes arising in the biofilm structure of Acidithiobacillus thiooxidans during a 120-h period of biooxidation. Results show that the biofilm first evolves from a low cell density structure (1 to 12 h) into a formation of microcolonies (24 to 120 h) and then finally becomes enclosed by a secondary compound matrix that includes pyrite (FeS2)-like, S n2-/S0, and As2S3 compounds, as shown by Raman and SEM-EDS. GDS analyses (concentration-depth profiles, i.e., 12 h) indicate significant differences for depth speciation between abiotic control and biooxidized surfaces, thus providing a quantitative assessment of surface-bulk changes across samples (i.e. reactivity and /or structure-activity relationship). Respectively, quantitative protein analyses and CLSM analyses suggest variations in the type of extracellular protein expressed and changes in the biofilm structure from hydrophilic (i.e., exopolysaccharides) to hydrophobic (i.e., lipids) due to arsenopyrite and cell interactions during the 120-h period of biooxidation. We suggest feasible environmental and industrial implications for arsenopyrite biooxidation based on the findings of this study.
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Affiliation(s)
- Hugo Ramírez-Aldaba
- Programa de Doctorado Interinstitucional en Ciencias Agropecuarias y Forestales, Universidad Juárez del Estado de Durango, Río Papaloapan y Blvd. Durango S/N, Col. Valle del Sur, 34120, Durango, DGO, Mexico
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango (UJED), Av. Veterinaria S/N, Circuito Universitario, Col. Valle del Sur, 34120, Durango, DGO, Mexico
| | - Jorge Vazquez-Arenas
- Centro Mexicano para la Producción más Limpia, Instituto Politécnico Nacional, Avenida Acueducto s/n, Col. La Laguna Ticomán, 07340, Ciudad de México, Mexico
| | - Fabiola S Sosa-Rodríguez
- Universidad Autónoma Metropolitana-Azcapotzalco, Av. San Pablo 180, Azcapotzalco, 02200, Ciudad de México, Mexico
| | - Donato Valdez-Pérez
- Instituto Politécnico Nacional, UPALM, Edif. Z-4 3er Piso, 07738, Ciudad de México, Mexico
| | - Estela Ruiz-Baca
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango (UJED), Av. Veterinaria S/N, Circuito Universitario, Col. Valle del Sur, 34120, Durango, DGO, Mexico
| | - Jessica Viridiana García-Meza
- Geomicrobiología, Facultad de Ingeniería, UASLP, Av. Sierra Leona 550, Lomas 2da, 78210, San Luis Potosí, SLP, Mexico
| | - Gabriel Trejo-Córdova
- Centro de Investigación y Desarrollo Tecnológico en Electroquímica (CIDETEQ), Parque Tecnológico Querétaro-Sanfandila, 76703, Pedro Escobedo, QRO, Mexico
| | - René H Lara
- Facultad de Ciencias Químicas, Universidad Juárez del Estado de Durango (UJED), Av. Veterinaria S/N, Circuito Universitario, Col. Valle del Sur, 34120, Durango, DGO, Mexico.
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47
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Huang D, Hua X, Xiu GL, Zheng YJ, Yu XY, Long YT. Secondary ion mass spectrometry: The application in the analysis of atmospheric particulate matter. Anal Chim Acta 2017; 989:1-14. [PMID: 28915935 DOI: 10.1016/j.aca.2017.07.042] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 07/12/2017] [Accepted: 07/18/2017] [Indexed: 12/13/2022]
Abstract
Currently, considerable attention has been paid to atmospheric particulate matter (PM) investigation due to its importance in human health and global climate change. Surface characterization, single particle analysis and depth profiling of PM is important for a better understanding of its formation processes and predicting its impact on the environment and human being. Secondary ion mass spectrometry (SIMS) is a surface technique with high surface sensitivity, high spatial resolution chemical imaging and unique depth profiling capabilities. Recent research shows that SIMS has great potential in analyzing both surface and bulk chemical information of PM. In this review, we give a brief introduction of SIMS working principle and survey recent applications of SIMS in PM characterization. Particularly, analyses from different types of PM sources by various SIMS techniques were discussed concerning their advantages and limitations. The future development and needs of SIMS in atmospheric aerosol measurement are proposed with a perspective in broader environmental sciences.
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Affiliation(s)
- Di Huang
- State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes, School of Resources & Environmental Engineering, East China University of Science and Technology, Shanghai 200237, PR China
| | - Xin Hua
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
| | - Guang-Li Xiu
- State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes, School of Resources & Environmental Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
| | - Yong-Jie Zheng
- College of Chemistry and Chemical Engineering, Qiqihar University, Qiqihar 161006, China
| | - Xiao-Ying Yu
- Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA 99354, USA.
| | - Yi-Tao Long
- Key Laboratory for Advanced Materials and School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, PR China
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48
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Manfredi M, Barberis E, Aceto M, Marengo E. Non-invasive characterization of colorants by portable diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and chemometrics. Spectrochim Acta A Mol Biomol Spectrosc 2017; 181:171-179. [PMID: 28363162 DOI: 10.1016/j.saa.2017.03.039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 03/14/2017] [Accepted: 03/17/2017] [Indexed: 06/07/2023]
Abstract
During the last years the need for non-invasive and non-destructive analytical methods brought to the development and application of new instrumentation and analytical methods for the in-situ analysis of cultural heritage objects. In this work we present the application of a portable diffuse reflectance infrared Fourier transform (DRIFT) method for the non-invasive characterization of colorants prepared according to ancient recipes and using egg white and Gum Arabic as binders. Approximately 50 colorants were analyzed with the DRIFT spectroscopy: we were able to identify and discriminate the most used yellow (i.e. yellow ochres, Lead-tin Yellow, Orpiment, etc.), red (i.e. red ochres, Hematite) and blue (i.e. Lapis Lazuli, Azurite, indigo) colorants, creating a complete DRIFT spectral library. The Principal Component Analysis-Discriminant Analysis (PCA-DA) was then employed for the colorants classification according to the chemical/mineralogical composition. The DRIFT analysis was also performed on a gouache painting of the artist Sutherland" and the colorants used by the painter were identified directly in-situ and in a non-invasive manner.
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Affiliation(s)
- Marcello Manfredi
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Viale Teresa Michel 11, Alessandria, Italy; ISALIT S.r.l., Via A. Canobio 4/6, Novara, NO, Italy
| | - Elettra Barberis
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Viale Teresa Michel 11, Alessandria, Italy; ISALIT S.r.l., Via A. Canobio 4/6, Novara, NO, Italy.
| | - Maurizio Aceto
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Viale Teresa Michel 11, Alessandria, Italy
| | - Emilio Marengo
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale, Viale Teresa Michel 11, Alessandria, Italy
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Kašpárková V, Humpolíček P, Capáková Z, Bober P, Stejskal J, Trchová M, Rejmontová P, Junkar I, Lehocký M, Mozetič M. Cell-compatible conducting polyaniline films prepared in colloidal dispersion mode. Colloids Surf B Biointerfaces 2017; 157:309-316. [PMID: 28601759 DOI: 10.1016/j.colsurfb.2017.05.066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/20/2017] [Accepted: 05/26/2017] [Indexed: 10/19/2022]
Abstract
Conducting polyaniline can be prepared and modified using several procedures, all of which can significantly influence its applicability in different fields of biomedicine or biotechnology. The modifications of surface properties are crucial with respect to the possible applications of this polymer in tissue engineering or as biosensors. Innovative technique for preparing polyaniline films via in-situ polymerization in colloidal dispersion mode using four stabilizers (poly-N-vinylpyrrolidone; sodium dodecylsulfate; Tween 20 and Pluronic F108) was developed. The surface energy, conductivity, spectroscopic features, and cell compatibility of thin polyaniline films were determined using contact-angle measurement, the van der Pauw method, Fourier-transform infrared spectroscopy, and assay conducted on mouse fibroblasts, respectively. The stabilizers significantly influenced not only the surface and electrical properties of the films but also their cell compatibility. Sodium dodecylsulfate seems preferentially to combine both the high conductivity and good cell compatibility. Moreover, the films with sodium dodecylsulfate were non-irritant for skin, which was confirmed by their in-vitro exposure to the 3D-reconstructed human tissue model.
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Affiliation(s)
- Věra Kašpárková
- Centre of Polymer Systems, Tomas Bata University in Zlin, 76001 Zlin, Czech Republic; Department of Fat, Surfactant, and Cosmetics Technology, Faculty of Technology, Tomas Bata University in Zlin, 760 01 Zlin, Czech Republic
| | - Petr Humpolíček
- Centre of Polymer Systems, Tomas Bata University in Zlin, 76001 Zlin, Czech Republic; Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, 760 01 Zlin, Czech Republic.
| | - Zdenka Capáková
- Centre of Polymer Systems, Tomas Bata University in Zlin, 76001 Zlin, Czech Republic
| | - Patrycja Bober
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6, Czech Republic
| | - Jaroslav Stejskal
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6, Czech Republic
| | - Miroslava Trchová
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, 162 06 Prague 6, Czech Republic
| | - Petra Rejmontová
- Centre of Polymer Systems, Tomas Bata University in Zlin, 76001 Zlin, Czech Republic; Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, 760 01 Zlin, Czech Republic
| | - Ita Junkar
- Department of Surface Engineering, Plasma Laboratory, Josef Stefan Institute, 1000 Ljubljana, Slovenia
| | - Marián Lehocký
- Centre of Polymer Systems, Tomas Bata University in Zlin, 76001 Zlin, Czech Republic
| | - Miran Mozetič
- Department of Surface Engineering, Plasma Laboratory, Josef Stefan Institute, 1000 Ljubljana, Slovenia
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50
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Al-Namnam NM, Kutty MG, Chai WL, Ha KO, Kim KH, Siar CH, Ngeow WC. An injectable poly(caprolactone trifumarate-gelatin microparticles) (PCLTF-GMPs) scaffold for irregular bone defects: Physical and mechanical characteristics. Mater Sci Eng C Mater Biol Appl 2017; 72:332-340. [PMID: 28024594 DOI: 10.1016/j.msec.2016.11.086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/09/2016] [Accepted: 11/23/2016] [Indexed: 10/20/2022]
Abstract
Recently, a modified form of a three-dimension (3D) porous poly(caprolactone-trifumarate) (PCLTF) scaffold has been produced using a fabrication technique that involves gelatin microparticles porogen leaching. This poly(caprolactone trifumarate-gelatin microparticles) (PCLTF-GMPs) scaffold has been shown to be biocompatible, more flowable clinically, and has a shorter degradation time as compared to its existing predecessors. In this report, a detailed characterization of this new scaffold was performed by testing its cytocompatibility, analyzing the surface topography, and understanding its thermal, physical and mechanical properties. The result showed that the PCLTF-GMPs has no critical cytotoxic effect. To confirm improvement, the surface properties were compared against the older version of PCLTF fabricated using salt porogen leaching. This PCLTF-GMPs scaffold showed no significant difference (unpaired t-test; p>0.05) in mechanical properties before and after gelatin leaching. However, it is mechanically weaker when compared to its predecessors. It has a high biodegradability rate of 16weeks. The pore size produced ranges from 40 to 300μm, and the RMS roughness is 613.7±236.9nm. These characteristics are condusive for osteoblast in-growth, as observed by the extension of filopodia across the macropores. Overall, this newly produced material has good thermal, physical and mechanical properties that complements its biocompatibility and ease of use.
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Affiliation(s)
- Nisreen Mohammed Al-Namnam
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Muralithran Govindan Kutty
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Wen Lin Chai
- Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kien Oon Ha
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kah Hwi Kim
- Department of Physiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Chong Huat Siar
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Wei Cheong Ngeow
- Department of Oral and Maxillofacial Clinical Sciences, Faculty of Dentistry, University of Malaya, 50603 Kuala Lumpur, Malaysia.
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