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Yang Y, Liao Y, Qing Y, Li H, Du J. Electrochemical DNA Biosensors with Dual-Signal Amplification Strategy for Highly Sensitive HPV 16 Detection. SENSORS (BASEL, SWITZERLAND) 2023; 23:7380. [PMID: 37687836 PMCID: PMC10490446 DOI: 10.3390/s23177380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/20/2023] [Accepted: 08/23/2023] [Indexed: 09/10/2023]
Abstract
Cervical cancer is an important topic in the study of global health issues, ranking fourth among women's cancer cases in the world. It is one of the nine major cancers that China is focusing on preventing and treating, and it is the only cancer that can be prevented through vaccination. Systematic and effective screening for human papilloma (HPV) infection, which is closely linked to the development of cervical cancer, can reduce cervical cancer incidence and mortality. In this paper, an electrochemical sensor was designed to detect HPV 16 using dual-signal amplification. An APTES-modified glassy carbon electrode was used for improved stability. Gold nanoparticles and a chain amplification reaction were combined for signal amplification. The limit of detection (LOD) of this electrochemical sensor was 1.731 × 10-16 mol/L, and the linear response of the target detector range was from 1.0 × 10-13 mol/L to 1.0 × 10-5 mol/L (R2 = 0.99232). The test of serum sample recovery showed that it has good anti-interference, and the performance of all aspects was improved to different degrees compared with the previous research from the team. The designed sensor is centered around the principles of low cost, high sensitivity and stability, which provides new ideas for the future development of cervical cancer prevention and electrochemical biosensors.
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Affiliation(s)
| | | | | | | | - Jie Du
- College of Materials Science and Engineering, Hainan University, Haikou 570228, China; (Y.Y.); (Y.L.); (Y.Q.); (H.L.)
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2
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Rajabimashhadi Z, Naghizadeh R, Zolriasatein A, Bagheri S, Mele C, Esposito Corcione C. Hydrophobic, Mechanical, and Physical Properties of Polyurethane Nanocomposite: Synergistic Impact of Mg(OH) 2 and SiO 2. Polymers (Basel) 2023; 15:polym15081916. [PMID: 37112062 PMCID: PMC10141087 DOI: 10.3390/polym15081916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/03/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
Polyurethane (PU) is one of the most well-known polymer coatings because of its favorable characteristics, which include its low density, nontoxicity, nonflammability, longevity, adhesion, simple manufacture, flexibility, and hardness. However, PU does come with several major drawbacks, among which are poor mechanical properties as well as low thermal and chemical stability, particularly in the high-temperature mode, where becomes gets flammable and loses adhesion ability. The limitations have inspired researchers to develop a PU composite to improve the weaknesses by adding different reinforcements. Magnesium hydroxide, having the ability to be produced with exceptional properties such as flammability, has consistently attracted the interest of researchers. Additionally, silica nanoparticles with high strength and hardness are one of the excellent reinforcements of polymers these days. The hydrophobic, physical, and mechanical properties of pure polyurethane and the composite type (nano, micro, and hybrid) fabricated with the drop casting method were examined in this study. 3-Aminopropyl triethoxysilane was applied as a functionalized agent. To confirm that hydrophilic particles turned into hydrophobic, FTIR analysis was carried out. The impact of size, percentage, and kind of fillers on different properties of PU/Mg(OH)2-SiO2 was then investigated using different analyses including spectroscopy and mechanical and hydrophobicity tests. The resultant observations demonstrated that different surface topographies can be obtained from the presence of particles of different sizes and percentages on the hybrid composite's surface. Surface roughness allowed for exceptionally high water contact angles, which confirmed the hybrid polymer coatings' superhydrophobic properties. According to the particle size and content, the distribution of fillers in the matrix also improved the mechanical properties.
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Affiliation(s)
- Zahra Rajabimashhadi
- School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran
| | - Rahim Naghizadeh
- School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran
| | - Ashkan Zolriasatein
- Non-Metallic Materials Research Department, Niroo Research Institute, Tehran 1466-5517, Iran
| | - Sonia Bagheri
- Department of Innovation Engineering, University of Salento, 73100 Lecce, Italy
| | - Claudio Mele
- Department of Innovation Engineering, University of Salento, 73100 Lecce, Italy
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3
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Menge H, Kim MW, Lee S, Park YT. Silicone-Based Multifunctional Thin Films with Improved Triboelectric and Sensing Performances via Chemically Interfacial Modification. ACS OMEGA 2023; 8:7135-7142. [PMID: 36844545 PMCID: PMC9948220 DOI: 10.1021/acsomega.3c00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
The development of triboelectric nanogenerators (TENGs) technology has advanced in recent years. However, TENG performance is affected by the screened-out surface charge density owing to the abundant free electrons and physical adhesion at the electrode-tribomaterial interface. Furthermore, the demand for flexible and soft electrodes is higher than that for stiff electrodes for patchable nanogenerators. This study introduces a chemically cross-linked (XL) graphene-based electrode with a silicone elastomer using hydrolyzed 3-aminopropylenetriethoxysilanes. The conductive graphene-based multilayered electrode was successfully assembled on a modified silicone elastomer using a cheap and eco-friendly layer-by-layer assembly method. As a proof-of-concept, the droplet-driven TENG with the chemically XL electrode of silicone elastomer exhibited an output power of approximately 2-fold improvement owing to its higher surface charge density than without XL. This chemically XL electrode of silicone elastomer film demonstrated remarkable stability and resistance to repeated mechanical deformations like bending and stretching. Moreover, due to the chemical XL effects, it was used as a strain sensor to detect subtle motions and exhibited high sensitivity. Thus, this cheap, convenient, and sustainable design approach can provide a platform for future multifunctional wearable electronic devices.
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Affiliation(s)
- Habtamu
Gebeyehu Menge
- Department
of Mechanical Engineering, Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin, Gyeonggi 17058, Republic of Korea
- School
of Mechanical Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Min Woo Kim
- Department
of Mechanical Engineering, Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin, Gyeonggi 17058, Republic of Korea
| | - Sangmin Lee
- School
of Mechanical Engineering, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, Republic of Korea
| | - Yong Tae Park
- Department
of Mechanical Engineering, Myongji University, 116 Myongji-ro, Cheoin-gu, Yongin, Gyeonggi 17058, Republic of Korea
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4
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Widyasari DA, Kristiani A, Randy A, Manurung RV, Dewi RT, Andreani AS, Yuliarto B, Jenie SNA. Optimized antibody immobilization on natural silica-based nanostructures for the selective detection of E. coli. RSC Adv 2022; 12:21582-21590. [PMID: 35975066 PMCID: PMC9346624 DOI: 10.1039/d2ra03143d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 07/12/2022] [Indexed: 11/21/2022] Open
Abstract
This study reports for the first time the surface modification of fluorescent nanoparticles derived from geothermal silica precipitate with Escherichia coli (E. coli) antibody. The immobilization of biomolecules on the inorganic surface has been carried out using two different pathways, namely the silanization and hydrosilylation reactions. The former applied (3-aminopropyl)triethoxysilane (APTES) as the crosslinker, while the latter used N-hydroxysuccinimide coupled with N-ethyl-N′-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC/NHS). Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FESEM-EDX), and fluorescence spectroscopy were used to confirm the chemical, physical, and optical properties of the surface-modified fluorescent silica nanoparticles (FSNPs). Based on the results of the FTIR, fluorescence spectroscopy and stability tests, the modified FSNPs with EDC/NHS with a ratio of 4 : 1 were proven to provide the optimum results for further conjugation with antibodies, affording the FSNP-Ab2 sample. The FSNP-Ab2 sample was further tested as a nanoplatform for the fluorescence-quenching detection of E. coli, which provided a linear range of 102 to 107 CFU mL−1 for E. coli with a limit of detection (LoD) of 1.6 × 102 CFU mL−1. The selectivity of the biosensor was observed to be excellent for E. coli compared to that for P. aeruginosa and S. typhimurium, with reductions in the maximum fluorescence intensity at 588 nm of 89.22%, 26.23%, and 54.06%, respectively. The inorganic nanostructure–biomolecule conjugation with optimized coupling agents showed promising analytical performance as a selective nanoplatform for detecting E. coli bacteria. This work describes for the first time the surface modification of natural-based fluorescent nanoparticles with antibodies as optical biosensing platforms.![]()
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Affiliation(s)
- Diaz Ayu Widyasari
- Research Centre for Chemistry, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Building 452, Serpong Tangerang Selatan 15314 Banten Indonesia .,Department of Physics Engineering, Research Centre for Nanosciences and Nanotechnology, Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40312 Jawa Barat Indonesia
| | - Anis Kristiani
- Research Centre for Chemistry, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Building 452, Serpong Tangerang Selatan 15314 Banten Indonesia
| | - Ahmad Randy
- Research Centre for Raw Material for Medicine and Traditional Medicine, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Serpong Tangerang Selatan 15314 Banten Indonesia
| | - Robeth V Manurung
- BRIN and ITB Collaboration Research Center for Biosensor and Biodevices Jl. Ganesha 10 Bandung 40132 Jawa Barat Indonesia.,Research Centre for Telecommunications, National Research and Innovation Agency (BRIN) Komplek LIPI Gd. 20, Jl. Cisitu Lama, Dago, Kecamatan Coblong Bandung 40135 Jawa Barat Indonesia
| | - Rizna Triana Dewi
- Research Centre for Raw Material for Medicine and Traditional Medicine, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Serpong Tangerang Selatan 15314 Banten Indonesia
| | - Agustina Sus Andreani
- Research Centre for Chemistry, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Building 452, Serpong Tangerang Selatan 15314 Banten Indonesia .,BRIN and ITB Collaboration Research Center for Biosensor and Biodevices Jl. Ganesha 10 Bandung 40132 Jawa Barat Indonesia
| | - Brian Yuliarto
- Department of Physics Engineering, Research Centre for Nanosciences and Nanotechnology, Institut Teknologi Bandung (ITB) Jl. Ganesha 10 Bandung 40312 Jawa Barat Indonesia.,BRIN and ITB Collaboration Research Center for Biosensor and Biodevices Jl. Ganesha 10 Bandung 40132 Jawa Barat Indonesia
| | - S N Aisyiyah Jenie
- Research Centre for Chemistry, National Research and Innovation Agency (BRIN) Kawasan PUSPIPTEK, Building 452, Serpong Tangerang Selatan 15314 Banten Indonesia .,BRIN and ITB Collaboration Research Center for Biosensor and Biodevices Jl. Ganesha 10 Bandung 40132 Jawa Barat Indonesia
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Protein Attachment Mechanism for Improved Functionalization of Affinity Monolith Chromatography (AMC). Molecules 2022; 27:molecules27144496. [PMID: 35889369 PMCID: PMC9323659 DOI: 10.3390/molecules27144496] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 12/10/2022] Open
Abstract
This work aims at understanding the attachment mechanisms and stability of proteins on a chromatography medium to develop more efficient functionalization methodologies, which can be exploited in affinity chromatography. In particular, the study was focused on the understanding of the attachment mechanisms of bovine serum albumin (BSA), used as a ligand model, and protein G on novel amine-modified alumina monoliths as a stationary phase. Protein G was used to develop a column for antibody purification. The results showed that, at lower protein concentrations (i.e., 0.5 to 1.0 mg·mL−1), protein attachment follows a 1st-order kinetics compatible with the presence of covalent binding between the monolith and the protein. At higher protein concentrations (i.e., up to 10 mg·mL−1), the data preferably fit a 2nd-order kinetics. Such a change reflects a different mechanism in the protein attachment which, at higher concentrations, seems to be governed by physical adsorption resulting in a multilayered protein formation, due to the presence of ligand aggregates. The threshold condition for the prevalence of physical adsorption of BSA was found at a concentration higher than 1.0 mg·mL−1. Based on this result, protein concentrations of 0.7 and 1.0 mg·mL−1 were used for the functionalization of monoliths with protein G, allowing a maximum attachment of 1.43 mg of protein G/g of monolith. This column was then used for IgG binding–elution experiments, which resulted in an antibody attachment of 73.5% and, subsequently, elution of 86%, in acidic conditions. This proved the potential of the amine-functionalized monoliths for application in affinity chromatography.
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Development of Methods for Specific Capture of Biological Targets on Aluminum Substrates: Application to Bacillus subtilis Spore Detection as a Model for Anthrax. SENSORS 2022; 22:s22093441. [PMID: 35591130 PMCID: PMC9106032 DOI: 10.3390/s22093441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/20/2022] [Accepted: 04/26/2022] [Indexed: 02/04/2023]
Abstract
Many (if not most) biosensors rely on functional silane coatings as a first step toward covalent immobilization of specific capture molecules. While methods for silanization of silica (SiO2) surfaces are very well developed, less has been done to develop and characterize silanization methods for alternative substrates, such as alumina (Al2O3). In particular, the behavior of Al2O3 coatings grown on aluminum under ambient conditions has not been studied. To address this issue, we have tested solution-phase deposition of two silanes on Al2O3 (3-aminopropyl triethoxysilane and 3-triethoxysilyl)propylsuccinic anhydride) and their applicability to analyte-specific biosensing. Contact angle measurements and imaging via Scanning Electron Microsopy (SEM) were employed to characterize surfaces. We find that 3-aminopropyl triethoxysilane produces well-behaved films and demonstrate that this surface can undergo further reaction with glutaraldehyde followed by an anti-Bacillus subtilis antibody to yield functionalized Al2O3 surfaces capable of specific capture of B. subtilis spores (a model of B. anthracis, the causative organism of Anthrax). In contrast, 3-triethoxysilyl)propylsuccinic anhydride did not behave well with Al/Al2O3 under the reaction conditions tested. In addition to providing specific protocols for Al/Al2O3 functionalization, this work highlights the importance of surface chemistry assessment in the development of new sensors.
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Surface Modification of Nanoporous Anodic Alumina during Self-Catalytic Atomic Layer Deposition of Silicon Dioxide from (3-Aminopropyl)Triethoxysilane. MATERIALS 2021; 14:ma14175052. [PMID: 34501141 PMCID: PMC8434165 DOI: 10.3390/ma14175052] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/26/2021] [Accepted: 08/30/2021] [Indexed: 12/27/2022]
Abstract
Changes associated to atomic layer deposition (ALD) of SiO2 from 3-aminopropyl triethoxysilane (APTES) and O3, on a nanoporous alumina structure, obtained by two-step electrochemical anodization in oxalic acid electrolyte (Ox sample) are analysed. A reduction of 16% in pore size for the Ox sample, used as support, was determined by SEM analysis after its coverage by a SiO2 layer (Ox+SiO2 sample), independently of APTES or O3 modification (Ox+SiO2/APTES and Ox+SiO2/APTES/O3 samples). Chemical surface modification was determined by X-ray photoelectron spectroscopy (XPS) technique during the different stages of the ALD process, and differences induced at the surface level on the Ox nanoporous alumina substrate seem to affect interfacial effects of both samples when they are in contact with an electrolyte solution according to electrochemical impedance spectroscopy (EIS) measurements, or their refraction index as determined by spectroscopic ellipsometry (SE) technique. However, no substantial differences in properties related to the nanoporous structure of anodic alumina (photoluminescent (PL) character or geometrical parameters) were observed between Ox+SiO2/APTES and Ox+SiO2/APTES/O3 samples.
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9
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Magnacca G, Neves Dos Santos F, Sadraei R. Bio-based Substances From Compost as Reactant and Active Phase for Selective Capture of Cationic Pollutants From Waste Water. Front Chem 2020; 8:550. [PMID: 32793547 PMCID: PMC7385075 DOI: 10.3389/fchem.2020.00550] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/28/2020] [Indexed: 11/13/2022] Open
Abstract
Alumina porous monoliths were successfully fabricated using a simple and reproducible synthesis dispersing gamma alumina phase from commercial boehmite (GAB) in water containing water-soluble bio-based substances (BBSs) obtained from composted biowaste. The wet mixture obtained was shaped in form of small spheres and then dried and calcined at 500°C in order to burn the organic matter and obtain mesoporous monoliths. They were successively functionalized with BBSs in order to introduce BBS functional groups and obtain an efficient adsorbing system. Therefore, in this work, BBSs acted as template/binder for the production of monoliths and as functionalizing agent of the produced monoliths. The reference powders, deeply studied in a published article (Sadraei et al., 2019b), and the monoliths of GAB before and after functionalization were characterized by means of x-ray diffraction to evidence their crystal structure, Fourier transform infrared spectroscopy for evaluating the presence of BBSs on the supports, thermogravimetric analysis to measure the thermal stability of the materials and quantify the functionalizing BBS amount immobilized on the supports, nitrogen adsorption at 77 K for the investigation of the surface area and porosity of the systems, and zeta potential measurements to analyze the effect of BBS immobilization on the surface charge of the supports and to predict the type of interaction, which can be established with substrates. Finally, the systems were applied in removal of pollutants with different charge, polarity, and molecular structure, such as dyes (crystal violet and acid orange 7) and contaminants of emerging concern (carbamazepine and atenolol). Only the cationic dye CV is captured by the adsorbing material, and this allows envisaging a possible use of the functionalized monoliths for selective adsorption of cationic substrates.
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Affiliation(s)
- Giuliana Magnacca
- Dipartimento di Chimica, Università di Torino, Turin, Italy.,Centre for Nanostructured Interfaces and Surfaces (NIS) Interdepartmental Centre, Università di Torino, Turin, Italy
| | | | - Razieh Sadraei
- Faculty of Science and Engineering, University of Wolverhampton, Wolverhampton, United Kingdom
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Photoelectrochemical assay for DNA hydroxymethylation determination based on the inhibited photoactivity of black TiO 2 nanosphere by ZnO. Mikrochim Acta 2020; 187:156. [PMID: 32025819 DOI: 10.1007/s00604-020-4131-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 01/20/2020] [Indexed: 10/25/2022]
Abstract
A photoelectrochemical method was proposed for DNA hydroxymethylation determination using black TiO2 (B-TiO2) nanosphere as photoactive material and ZnO as photoactivity inhibitor. After hydroxymethylated DNA (5hmC-DNA) was captured on the probe modified B-TiO2/ITO electrode surface through hybridization, a glycosyl can be then transferred from uridine diphosphoglucose to 5hmC-DNA and formed a covalent structure with -CH2OH in the presence of T4 β-glucosyltransferase (β-GT). Afterwards, based on a series of covalent reaction, amino functionalized ZnO nanoparticles are further immobilized to the surface of the electrode. Due to the capacity to expend the irradiation light and the photogenerated electron of electron donor, the modified ZnO nanoparticles can result in a decreased photocurrent. The developed method shows wide linear ranges from 0.05-200 nM for hydroxymethylated DNA and 1-220 unit·mL-1 for T4-β-glucosyltransferase. The corresponding determination limits were 0.013 nM and 0.24 unit·mL-1, respectively. The enzyme activity inhibited by 4-phenylimidazole was evaluated. This photoelectrochemical method shows high specificity for 5hmC-DNA (compared to 5fC, 5mC, m6A, control) and β-GT (compared to β-AGT, UGT2B7), and shows excellent stability for testing 5hmC (RSD = 2.75%). Graphical abstractSchematic representation of photoelectrochemical method for DNA hydroxymethylation and β-glucosyltransferase detection based on the glycosylation reaction of -CH2OH in 5-hydroxymethylcytosine and the inhibition activity of ZnO to the photoactivity of black TiO2 nanospheres.
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Ultrasound-Assisted Preparation of Chitosan/Nano-Activated Carbon Composite Beads Aminated with (3-Aminopropyl)Triethoxysilane for Adsorption of Acetaminophen from Aqueous Solutions. Polymers (Basel) 2019; 11:polym11101701. [PMID: 31623271 PMCID: PMC6835286 DOI: 10.3390/polym11101701] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 12/11/2022] Open
Abstract
A composite chitosan/nano-activated carbon (CS-NAC) aminated by (3-aminopropyl)triethoxysilane (APTES) was prepared in the form of beads and applied for the removal of acetaminophen from aqueous solutions. NAC and APTES concentrations were optimized to obtain a suitable adsorbent structure for enhanced removal of the pharmaceutical. The aminated adsorbent (CS-NAC-APTES beads) prepared with 40% w/w NAC and 2% v/v APTES showed higher adsorption capacity (407.83 mg/g) than CS-NAC beads (278.4 mg/g). Brunauer–Emmett–Teller (BET) analysis demonstrated that the surface area of the CS-NAC-APTES beads was larger than that of CS-NAC beads (1.16 times). The adsorption process was well fitted by the Freundlich model (R2 > 0.95), suggesting a multilayer adsorption. The kinetic study also substantiated that the pseudo-second-order model (R2 > 0.98) was in better agreement with the experimental data. Finally, it was proved that the prepared beads can be recycled (by washing with NaOH solution) at least 5 times before detectable performance loss.
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