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Diaa AA, El-Mahallawy N, Shoeib M, Mouillard F, Ferté T, Masson P, Carradò A. Biodegradable PMMA coated Zn-Mg alloy with bimodal grain structure for orthopedic applications - A promising alternative. Bioact Mater 2024; 39:479-491. [PMID: 38883318 PMCID: PMC11179251 DOI: 10.1016/j.bioactmat.2024.05.031] [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: 12/19/2023] [Revised: 05/01/2024] [Accepted: 05/16/2024] [Indexed: 06/18/2024] Open
Abstract
The study examines the impact of microstructure and polymethyl methacrylate (PMMA) grafting on the degradability of Zn-Mg alloys. The mechanical properties of a Zn alloy containing 0.68 wt% Mg and extruded at 200 °C are enhanced for degradable load-bearing applications, addressing a crucial need in the field. The material exhibits a bimodal grain size distribution that is random texture, consisting of secondary phases, grains, and sub-grains. With an elongation to failure of 16 %, the yield and ultimate tensile strengths are 325.9 and 414.5 MPa, respectively, and the compressive yield strength is 450.5 MPa. The "grafting-from" method was used to coat a few micrometers thick of PMMA on both bulk and scaffold Zn alloys to mitigate the corrosion rate. The last one is a porous structure, with a porosity of 65.8 %, considered as in the first approach of an orthopedic implant. After being immersed for 720 h, the PMMA-grafted bulk alloy's corrosion rate decreased from 0.43 to 0.25 mm/y. Similarly, the scaffold alloy's corrosion rate reduced from 1.24 to 0.49 mm/y. These results indicate that the method employed could be used for future orthopedic applications.
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Affiliation(s)
- Alia A Diaa
- Design and Production Engineering Department, Faculty of Engineering, Ain Shams University, Cairo, 11517, Egypt
- Department of Design and Production Engineering, Faculty of Engineering and Materials Science, German University in Cairo, Cairo, 11835, Egypt
| | - Nahed El-Mahallawy
- Design and Production Engineering Department, Faculty of Engineering, Ain Shams University, Cairo, 11517, Egypt
- Department of Design and Production Engineering, Faculty of Engineering and Materials Science, German University in Cairo, Cairo, 11835, Egypt
| | - Madiha Shoeib
- Central Metallurgical Research and Development Institute, El Tebbin, Cairo, 11722, Egypt
| | - Flavien Mouillard
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000, Strasbourg, France
| | - Tom Ferté
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000, Strasbourg, France
| | - Patrick Masson
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000, Strasbourg, France
| | - Adele Carradò
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000, Strasbourg, France
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Xu Y, Stanko AM, Cerione CS, Lohrey TD, McLeod E, Stoltz BM, Su J. Low Part-Per-Trillion, Humidity Resistant Detection of Nitric Oxide Using Microtoroid Optical Resonators. ACS APPLIED MATERIALS & INTERFACES 2024; 16:5120-5128. [PMID: 38240231 DOI: 10.1021/acsami.3c16012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
The nitric oxide radical plays pivotal roles in physiological as well as atmospheric contexts. Although the detection of dissolved nitric oxide in vivo has been widely explored, highly sensitive (i.e., low part-per-trillion level), selective, and humidity-resistant detection of gaseous nitric oxide in air remains challenging. In the field, humidity can have dramatic effects on the accuracy and selectivity of gas sensors, confounding data, and leading to overestimation of gas concentration. Highly selective and humidity-resistant gaseous NO sensors based on laser-induced graphene were recently reported, displaying a limit of detection (LOD) of 8.3 ppb. Although highly sensitive (LOD = 590 ppq) single-wall carbon nanotube NO sensors have been reported, these sensors lack selectivity and humidity resistance. In this report, we disclose a highly sensitive (LOD = 2.34 ppt), selective, and humidity-resistant nitric oxide sensor based on a whispering-gallery mode microtoroid optical resonator. Excellent analyte selectivity was enabled via novel ferrocene-containing polymeric coatings synthesized via reversible addition-fragmentation chain-transfer polymerization. Utilizing a frequency locked optical whispering evanescent resonator system, the microtoroid's real-time resonance frequency shift response to nitric oxide was tracked with subfemtometer resolution. The lowest concentration experimentally detected was 6.4 ppt, which is the lowest reported to date. Additionally, the performance of the sensor remained consistent across different humidity environments. Lastly, the impact of the chemical composition and molecular weight of the novel ferrocene-containing polymeric coatings on sensing performance was evaluated. We anticipate that our results will have impact on a wide variety of fields where NO sensing is important such as medical diagnostics through exhaled breath, determination of planetary habitability, climate change, air quality monitoring, and treating cardiovascular and neurological disorders.
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Affiliation(s)
- Yinchao Xu
- Wyant College of Optical Sciences, The University of Arizona, Tucson, Arizona 85721, United States
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Allison M Stanko
- The Warren and Catherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Chloe S Cerione
- The Warren and Catherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Trevor D Lohrey
- The Warren and Catherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Euan McLeod
- Wyant College of Optical Sciences, The University of Arizona, Tucson, Arizona 85721, United States
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Brian M Stoltz
- The Warren and Catherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Judith Su
- Wyant College of Optical Sciences, The University of Arizona, Tucson, Arizona 85721, United States
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
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Reulbach M, Evers P, Emonde C, Behnsen H, Nürnberger F, Windhagen H, Jakubowitz E. Implications of ageing effects on thermal and mechanical properties of PMMA-based bone cement for THA revision surgery. J Mech Behav Biomed Mater 2023; 148:106218. [PMID: 37931550 DOI: 10.1016/j.jmbbm.2023.106218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/27/2023] [Accepted: 10/30/2023] [Indexed: 11/08/2023]
Abstract
Loosening and infection are the main reasons for revision surgery in total hip arthroplasty (THA). Removing partially detached cemented implant components during revision surgery remains challenging and poses the risk of periprosthetic bone damage. A promising approach for a gentler removal of partially detached prostheses involves softening the PMMA-based bone cement by heating it above its glass transition temperature (TG), thus loosening the implant-cement bond. It is assumed that the TG of PMMA-based bone cement decreases in-vivo due to the gradual absorption of body fluid. Reliable data on TG are essential to develop a heat-based method for removing cemented implant components during revision surgery. The effect of water absorption was investigated in-vitro by ageing PMMA-based bone cement samples for different periods up to 56 days in both Ringer's solution (37 °C) and air (37 °C and 30% humidity). Subsequently, the TG and Vicat softening temperatures of the samples were determined by differential scanning calorimetry and Vicat tests, respectively, according to prescribed methods. Over the entire ageing period, i.e. comparing one day of ageing in air and 56 days in Ringer's solution, the Vicat softening temperature dropped by 16 °C, while the TG dropped by 10 °C for Palacos® R PMMA-based bone cement. Water absorption over time correlated significantly with the Vicat softening temperature until saturation of the PMMA-based bone cement was reached. Based on the TG and Vicat softening temperature measurements, it can be assumed that in body-aged bone cement, an optimal softening can be achieved within a temperature range of 85 °C-93 °C to loosen the bond between the PMMA-based bone cement mantle and the prosthesis stem. These findings may pave the way for a gentler removal of the implant in revision THA.
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Affiliation(s)
- Magnus Reulbach
- Laboratory for Biomechanics and Biomaterials (LBB), Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, 30625, Hannover, Germany
| | - Patrick Evers
- Institute of Materials Science (Werkstoffkunde), Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany
| | - Crystal Emonde
- Laboratory for Biomechanics and Biomaterials (LBB), Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, 30625, Hannover, Germany
| | - Hannah Behnsen
- Institute of Plastics and Circular Economy, Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany
| | - Florian Nürnberger
- Institute of Materials Science (Werkstoffkunde), Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany
| | - Henning Windhagen
- Laboratory for Biomechanics and Biomaterials (LBB), Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, 30625, Hannover, Germany
| | - Eike Jakubowitz
- Laboratory for Biomechanics and Biomaterials (LBB), Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, 30625, Hannover, Germany.
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Sui K, Meneghetti M, Li G, Ioannou A, Abdollahian P, Kalli K, Nielsen K, Berg RW, Markos C. In vivo brain temperature mapping using polymer optical fiber Bragg grating sensors. OPTICS LETTERS 2023; 48:4225-4228. [PMID: 37581998 DOI: 10.1364/ol.498031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 07/21/2023] [Indexed: 08/17/2023]
Abstract
Variation of the brain temperature is strongly affected by blood flow, oxygen supply, and neural cell metabolism. Localized monitoring of the brain temperature is one of the most effective ways to correlate brain functions and diseases such as stroke, epilepsy, and mood disorders. While polymer optical fibers (POFs) are considered ideal candidates for temperature sensing in the brain, they have never been used so far in vivo. Here, we developed for the first, to the best of our knowledge, time an implantable probe based on a microstructured polymer optical fiber Bragg grating (FBG) sensor for intracranial brain temperature mapping. The temperature at different depths of the brain (starting from the cerebral cortex) and the correlation between the brain and body core temperature of a rat were recorded with a sensitivity of 33 pm/°C and accuracy <0.2°C. Our in vivo experimental results suggest that the proposed device can achieve real-time and high-resolution local temperature measurement in the brain, as well as being integrated with existing neural interfaces.
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Hniopek J, Meurer J, Zechel S, Schmitt M, Hager MD, Popp J. Molecular in situ monitoring of the pH-triggered response in adaptive polymers by two-dimensional Raman micro-correlation-spectroscopy. Chem Sci 2023; 14:7248-7255. [PMID: 37416726 PMCID: PMC10321532 DOI: 10.1039/d3sc01455j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/02/2023] [Indexed: 07/08/2023] Open
Abstract
Stimuli-responsive polymers can switch specific physical properties in response to a change of the environmental conditions. This behavior offers unique advantages in applications where adaptive materials are needed. To tune the properties of stimuli-responsive polymers, a detailed understanding of the relationship between the applied stimulus and changes in molecular structure as well as the relationship between the latter and macroscopic properties is required, which until now has required laborious methods. Here, we present a straightforward way to investigate the progressing trigger, the change of the chemical composition of the polymer and the macroscopic properties simultaneously. Thereby, the response behavior of the reversible polymer is studied in situ with molecular sensitivity and spatial as well as temporal resolution utilizing Raman micro-spectroscopy. Combined with two-dimensional correlation analysis (2DCOS), this method reveals the stimuli-response on a molecular level and determines the sequence of changes and the diffusion rate inside the polymer. Due to the label-free and non-invasive approach, it is furthermore possible to combine this method with the investigation of macroscopic properties revealing the response of the polymer to the external stimulus on both the molecular and the macroscopic level.
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Affiliation(s)
- Julian Hniopek
- Department Spectroscopy & Imaging, Leibniz Institute of Photonic Technology Albert-Einstein-Str. 9 0775 Jena Germany
- Institute of Physical Chemistry (IPC), Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
- Abbe Center of Photonics, Friedrich Schiller University Jena Albert-Einstein-Str. 6 07745 Jena Germany
| | - Josefine Meurer
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena Humboldtstr. 10 07743 Jena Germany
- Jena Center of Soft Matter (JCSM), Friedrich Schiller University Jena Philosophenweg 7 07743 Jena Germany
| | - Stefan Zechel
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena Humboldtstr. 10 07743 Jena Germany
- Jena Center of Soft Matter (JCSM), Friedrich Schiller University Jena Philosophenweg 7 07743 Jena Germany
| | - Michael Schmitt
- Institute of Physical Chemistry (IPC), Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
- Abbe Center of Photonics, Friedrich Schiller University Jena Albert-Einstein-Str. 6 07745 Jena Germany
| | - Martin D Hager
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena Humboldtstr. 10 07743 Jena Germany
- Jena Center of Soft Matter (JCSM), Friedrich Schiller University Jena Philosophenweg 7 07743 Jena Germany
| | - Jürgen Popp
- Department Spectroscopy & Imaging, Leibniz Institute of Photonic Technology Albert-Einstein-Str. 9 0775 Jena Germany
- Institute of Physical Chemistry (IPC), Friedrich Schiller University Jena Helmholtzweg 4 07743 Jena Germany
- Abbe Center of Photonics, Friedrich Schiller University Jena Albert-Einstein-Str. 6 07745 Jena Germany
- Jena Center of Soft Matter (JCSM), Friedrich Schiller University Jena Philosophenweg 7 07743 Jena Germany
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Zhou H, Niu H, Wang H, Lin T. Self-Healing Superwetting Surfaces, Their Fabrications, and Properties. Chem Rev 2023; 123:663-700. [PMID: 36537354 DOI: 10.1021/acs.chemrev.2c00486] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The research on superwetting surfaces with a self-healing function against various damages has progressed rapidly in the recent decade. They are expected to be an effective approach to increasing the durability and application robustness of superwetting materials. Various methods and material systems have been developed to prepare self-healing superwetting surfaces, some of which mimic natural superwetting surfaces. However, they still face challenges, such as being workable only for specific damages, external stimulation to trigger the healing process, and poor self-healing ability in the water, marine, or biological systems. There is a lack of fundamental understanding as well. This article comprehensively reviews self-healing superwetting surfaces, including their fabrication strategies, essential rules for materials design, and self-healing properties. Self-healing triggered by different external stimuli is summarized. The potential applications of self-healing superwetting surfaces are highlighted. This article consists of four main sections: (1) the functional surfaces with various superwetting properties, (2) natural self-healing superwetting surfaces (i.e., plants, insects, and creatures) and their healing mechanism, (3) recent research development in various self-healing superwetting surfaces, their preparation, wetting properties in the air or liquid media, and healing mechanism, and (4) the prospects including existing challenges, our views and potential solutions to the challenges, and future research directions.
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Affiliation(s)
- Hua Zhou
- College of Textiles & Clothing, State Key Laboratory for Biofibers and Eco-textiles, Collaborative Innovation Centre for Eco-textiles of Shandong Province, Qingdao University, Qingdao 266071, China
| | - Haitao Niu
- College of Textiles & Clothing, State Key Laboratory for Biofibers and Eco-textiles, Collaborative Innovation Centre for Eco-textiles of Shandong Province, Qingdao University, Qingdao 266071, China
| | - Hongxia Wang
- Institute for Frontier Materials, Deakin University, Geelong Victoria 3216, Australia.,Institute for Nanofiber Intelligent Manufacture and Applications, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China
| | - Tong Lin
- Institute for Nanofiber Intelligent Manufacture and Applications, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China.,State Key Laboratory of Separation Membranes and Membrane Processes, School of Textile Science and Engineering, Tiangong University, Tianjin 300387, China
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Diaa AA, El-Mahallawy N, Shoeib M, Lallemand N, Mouillard F, Masson P, Carradò A. Effect of Mg Addition and PMMA Coating on the Biodegradation Behaviour of Extruded Zn Material. MATERIALS (BASEL, SWITZERLAND) 2023; 16:707. [PMID: 36676444 PMCID: PMC9863199 DOI: 10.3390/ma16020707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 12/29/2022] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
Although zinc (Zn) is one of the elements with the greatest potential for biodegradable uses, pure Zn does not have the ideal mechanical or degrading properties for orthopaedic applications. The current research aims at studying the microstructure and corrosion behaviour of pure Zn (used as a reference material) and Zn alloyed with 1.89 wt.% magnesium (Mg), both in their extruded states as well as after being coated with polymethyl methacrylate (PMMA). The grafting-from approach was used to create a PMMA covering. The "grafting-from" method entails three steps: the alkali activation of the alloys, their functionalization with an initiator of polymerization through a phosphonate-attaching group, and the surface-initiated atom transfer radical polymerisation (SI-ATRP) to grow PMMA chains. Electrochemical and immersion corrosion tests were carried out in a simulated body fluid (SBF), and both confirmed the enhanced corrosion behaviour obtained after coating. The electrochemical test revealed a decrease in the degradation rate of the alloy from 0.37 ± 0.14 mm/y to 0.22 ± 0.01 mm/y. The immersion test showed the ability of complete protection for 240 h. After 720 h of immersion, the coated alloy displays minute crevice corrosion with very trivial pitting compared to the severe localized (galvanic and pitting) corrosion type that was detected in the bare alloy.
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Affiliation(s)
- Alia A. Diaa
- Design and Production Engineering Department, Faculty of Engineering, Ain Shams University, Cairo 11517, Egypt
- Department of Design and Production Engineering, Faculty of Engineering and Materials Science, German University in Cairo, Cairo 11835, Egypt
| | - Nahed El-Mahallawy
- Design and Production Engineering Department, Faculty of Engineering, Ain Shams University, Cairo 11517, Egypt
- Department of Design and Production Engineering, Faculty of Engineering and Materials Science, German University in Cairo, Cairo 11835, Egypt
| | - Madiha Shoeib
- Central Metallurgical Research and Development Institute, El Tebbin, Cairo 11722, Egypt
| | - Nicolas Lallemand
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000 Strasbourg, France
| | - Flavien Mouillard
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000 Strasbourg, France
| | - Patrick Masson
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000 Strasbourg, France
| | - Adele Carradò
- Institut de Physique et Chimie des Matériaux de Strasbourg, IPCMS, UMR 7504 CNRS, Université de Strasbourg, 67000 Strasbourg, France
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Effect of commonly used lavage solutions on the polymerization of bone cement. Orthop Traumatol Surg Res 2022; 108:103243. [PMID: 35158106 DOI: 10.1016/j.otsr.2022.103243] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/22/2021] [Accepted: 02/04/2021] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Little is known about the impact irrigation solutions have on the material properties of cement used in hip and knee arthroplasty. We sought to compare the effect of three commonly used lavage solutions on cement polymerization. METHODS Ten groups were used for cure and mechanical testing: two cement controls, and eight cement groups mixed with test solutions. Test solutions included a commercially available benzalkonium chloride/citric acid solution (BCS), chlorhexidine gluconate (0.05%) (CHG), povidone-iodine 0.35%, and normal saline added at cement mixing onset. Cement dough-time, set-time, and compression testing were performed following The American Society for Testing and Materials guidelines. RESULTS Povidone-iodine had shorter dough-time (1min 34sec, sd 1min 5sec) versus controls (1min 56sec, sd 1min 35sec), p=0.0419. Cement exposed to all lavage samples had significantly reduced set-time. Compressive strength was reduced for all surgical lavages (p<0.001). Pairwise testing revealed that all lavage treatments reduced offset strength versus controls (p<0.001). CONCLUSION Bone cement exposed to lavage solutions during the cement mixing-phase showed accelerated set-times and decreased compressive strength. If bone is not dry, and cement has not finished mixing at the time of application, cement curing time may be shortened. Additionally, bone cement should reach dough phase prior to pre-closure surgical lavage. LEVEL OF EVIDENCE III; case control study.
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Sim Y, Chae Y, Kwon SY. Recent advances in metallic transition metal dichalcogenides as electrocatalysts for hydrogen evolution reaction. iScience 2022; 25:105098. [PMID: 36157572 PMCID: PMC9490594 DOI: 10.1016/j.isci.2022.105098] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Layered metallic transition metal dichalcogenides (MTMDs) exhibit distinctive electrical and catalytic properties to drive basal plane activity, and, therefore, they have emerged as promising alternative electrocatalysts for sustainable hydrogen evolution reactions (HERs). A key challenge for realizing MTMDs-based electrocatalysts is the controllable and scalable synthesis of high-quality MTMDs and the development of engineering strategies that allow tuning their electronic structures. However, the lack of a method for the direct synthesis of MTMDs retaining the structural stability limits optimizing the structural design for the next generation of robust electrocatalysts. In this review, we highlight recent advances in the synthesis of MTMDs comprising groups VB and VIB and various routes for structural engineering to enhance the HER catalytic performance. Furthermore, we provide insight into the potential future directions and the development of MTMDs with high durability as electrocatalysts to generate green hydrogen through water-splitting technology.
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Affiliation(s)
- Yeoseon Sim
- Department of Materials Science and Engineering & Center for Future Semiconductor Technology (FUST), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Yujin Chae
- Department of Materials Science and Engineering & Center for Future Semiconductor Technology (FUST), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
| | - Soon-Yong Kwon
- Department of Materials Science and Engineering & Center for Future Semiconductor Technology (FUST), Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
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Molecular Dynamics and Structure of Poly(Methyl Methacrylate) Chains Grafted from Barium Titanate Nanoparticles. Molecules 2022; 27:molecules27196372. [PMID: 36234912 PMCID: PMC9571223 DOI: 10.3390/molecules27196372] [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: 07/31/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 12/04/2022] Open
Abstract
Core−shell nanocomposites comprising barium titanate, BaTiO3 (BTO), and poly(methyl methacrylate) (PMMA) chains grafted from its surface with varied grafting densities were prepared. BTO nanocrystals are high-k inorganic materials, and the obtained nanocomposites exhibit enhanced dielectric permittivity, as compared to neat PMMA, and a relatively low level of loss tangent in a wide range of frequencies. The impact of the molecular dynamics, structure, and interactions of the BTO surface on the polymer chains was investigated. The nanocomposites were characterized by broadband dielectric and vibrational spectroscopies (IR and Raman), transmission electron microscopy, differential scanning calorimetry, and nuclear magnetic resonance. The presence of ceramic nanoparticles in core–shell composites slowed down the segmental dynamic of PMMA chains, increased glass transition temperature, and concurrently increased the thermal stability of the organic part. It was also evidenced that, in addition to segmental dynamics, local β relaxation was affected. The grafting density influenced the self-organization and interactions within the PMMA phase, affecting the organization on a smaller size scale of polymeric chains. This was explained by the interaction of the exposed surface of nanoparticles with polymer chains.
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Buescher J, John T, Boehm AK, Weber L, Abdel-Hafez SM, Wagner C, Kraus T, Gallei M, Schneider M. A precise nanoparticle quantification approach using microfluidics and single-particle tracking. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Li S, Yang F, Xiang K, Chen J, Zhang Y, Wang J, Sun J, Li Y. A Multifunctional Microspheric Soil Conditioner Based on Chitosan-Grafted Poly(acrylamide- co-acrylic acid)/Biochar. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5717-5729. [PMID: 35442693 DOI: 10.1021/acs.langmuir.2c00317] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A multifunctional microspheric soil conditioner based on chitosan-grafted poly(acrylamide-co-acrylic acid)/biochar [CS-g-P(AM-co-AA)/BC] was prepared. First, the P(AM-co-AA) was synthesized and successfully grafted onto CS, and the three-dimensional network structure of microspheres was formed with N,N-methylenebis(acrylamide) as the cross-linking agent according to the inverse suspension polymerization method. Meanwhile, BC and urea were encapsulated into the body of microspheres during the polymerization. The structure of the microspheres was analyzed by Fourier transform infrared spectroscopy, polarized optical microscopy, and scanning electron microscopy, and the mechanism of adsorption of Cu2+ on the microspheres was investigated by X-ray photoelectron spectroscopy. Furthermore, the experimental results demonstrated the excellent water absorption and retention capabilities of microspheres, and the release rate of urea was dramatically reduced. Importantly, the introduction of BC significantly enhanced the adsorption performance of the microspheres with respect to heavy metal ions. Consequently, the multifunctional soil conditioner held promise for use in soil improvement and agricultural production.
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Affiliation(s)
- Shuhong Li
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Fan Yang
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Kailing Xiang
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Jiacheng Chen
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Ye Zhang
- Université de Paris, ITODYS, CNRS, UMR 7086, 15 rue J.-A. de Baïf, F-75013 Paris, France
| | - Jincheng Wang
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, P. R. China
| | - Jibo Sun
- Wopu New Material Technology (Shanghai) Company, Ltd., Shanghai 201600, P. R. China
| | - Yuan Li
- Jiangsu Lvhong Landscaping Engineering Company, Ltd., Jiangsu 226100, P. R. China
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Talianov PM, Yakubova AA, Bukreeva A, Masharin M, Eliseev IE, Zelenkov L, Muslimov AR, Bukatin A, Gordeeva A, Kudryavtseva V, Makarov SV, Sukhorukov GB, Timin AS, Zyuzin MV. Incorporation of Perovskite Nanocrystals into Polymer Matrix for Enhanced Stability in Biological Media: In Vitro and In Vivo Studies. ACS APPLIED BIO MATERIALS 2022; 5:2411-2420. [PMID: 35426657 DOI: 10.1021/acsabm.2c00295] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The outstanding optical properties and multiphoton absorption of lead halide perovskites make them promising for use as fluorescence tags in bioimaging applications. However, their poor stability in aqueous media and biological fluids significantly limits their further use for in vitro and in vivo applications. In this work, we have developed a universal approach for the encapsulation of lead halide perovskite nanocrystals (PNCs) (CsPbBr3 and CsPbI3) as water-resistant fluorescent markers, which are suitable for fluorescence bioimaging. The obtained encapsulated PNCs demonstrate bright green emission at 510 nm (CsPbBr3) and red emission at 688 nm (CsPbI3) under one- and two-photon excitation, and they possess an enhanced stability in water and biological fluids (PBS, human serum) for a prolonged period of time (1 week). Further in vitro and in vivo experiments revealed enhanced stability of PNCs even after their introduction directly into the biological microenvironment (CT26 cells and DBA mice). The developed approach allows making a step toward stable, low-cost, and highly efficient bioimaging platforms that are spectrally tunable and have narrow emission.
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Affiliation(s)
- Pavel M Talianov
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation
| | - Anastasia A Yakubova
- Peter The Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St. Petersburg 195251, Russian Federation.,Laboratory of Renewable Energy Sources, Alferov University, Khlopin St. 8/3, St. Petersburg 194021, Russian Federation
| | - Anastasia Bukreeva
- Peter The Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St. Petersburg 195251, Russian Federation
| | - Mikhail Masharin
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation
| | - Igor E Eliseev
- Laboratory of Renewable Energy Sources, Alferov University, Khlopin St. 8/3, St. Petersburg 194021, Russian Federation
| | - Lev Zelenkov
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation
| | - Albert R Muslimov
- Peter The Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St. Petersburg 195251, Russian Federation.,Laboratory of Renewable Energy Sources, Alferov University, Khlopin St. 8/3, St. Petersburg 194021, Russian Federation
| | - Anton Bukatin
- Laboratory of Renewable Energy Sources, Alferov University, Khlopin St. 8/3, St. Petersburg 194021, Russian Federation
| | - Alexandra Gordeeva
- Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation
| | - Valeriya Kudryavtseva
- School of Engineering and Material Science, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Sergey V Makarov
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation
| | - Gleb B Sukhorukov
- Skolkovo Institute of Science and Technology, Moscow 143026, Russian Federation.,School of Engineering and Material Science, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Alexander S Timin
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation.,Peter The Great St. Petersburg Polytechnic University, Polytechnicheskaya 29, St. Petersburg 195251, Russian Federation.,Research School of Chemical and Biomedical Engineering, National Research Tomsk Polytechnic University, Lenin Avenue 30, Tomsk 634050, Russia
| | - Mikhail V Zyuzin
- School of Physics and Engineering, ITMO University, Lomonosova 9, 197101, St. Petersburg, Russian Federation
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14
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Chamlagain B, Khondaker SI. Rapid Degradation of the Electrical Properties of 2D MoS 2 Thin Films under Long-Term Ambient Exposure. ACS OMEGA 2021; 6:24075-24081. [PMID: 34568686 PMCID: PMC8459407 DOI: 10.1021/acsomega.1c03522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Indexed: 06/08/2023]
Abstract
The MoS2 thin film has attracted a lot of attention due to its potential applications in flexible electronics, sensors, catalysis, and heterostructures. Understanding the effect of long-term ambient exposure on the electrical properties of the thin film is important for achieving many overreaching goals of this material. Here, we report for the first time a systematic study of electrical property variation and stability of MoS2 thin films under ambient exposure of up to a year. The MoS2 thin films were grown via the sulfurization of 6 nm thick molybdenum films. We found that the resistance of the samples increases by 114% just in 4 weeks and 430% in 4 months and they become fully insulated in a year of ambient exposure. The dual-sweep current-voltage (I-V) characteristic shows hysteretic behavior for a 4-month-old sample which further exhibits pronounced nonlinear I-V curves and hysteretic behavior after 8 months. The X-ray photoelectron spectroscopy measurements show that the MoS2 thin film gradually oxidizes and 13.1% of MoO3 and 11.8% oxide of sulfur were formed in 4 months, which further increased to 23.1 and 12.7% in a year, respectively. The oxide of the sulfur peak was not reported in any previous stability studies of exfoliated and chemical vapor deposition-grown MoS2, suggesting that the origin of this peak is related to the distinct crystallinity of the MoS2 thin film due to its smaller grain sizes, abundant grain boundaries, and exposed edges. Raman studies show the broadening of E2g 1 and A1g peaks with increasing exposure time, suggesting an increase in the disorder in MoS2. It is also found that coating the MoS2 thin film with polymethylmethacrylate can effectively prevent the electrical property degradation, showing only a 6% increase in resistance in 4 months and 40% over a year of ambient exposure.
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Affiliation(s)
- Bhim Chamlagain
- NanoScience
Technology Center and Department of Physics, University of Central Florida, Orlando, Florida 32826, United States
| | - Saiful I. Khondaker
- NanoScience
Technology Center and Department of Physics, University of Central Florida, Orlando, Florida 32826, United States
- School
of Electrical Engineering and Computer Science, University of Central Florida, Orlando, Florida 32826, United States
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15
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Grad P, Agmo Hernández V, Edwards K. Avoiding artifacts in liposome leakage measurements via cuvette- and liposome-surface modifications. J Liposome Res 2021; 32:237-249. [PMID: 34369250 DOI: 10.1080/08982104.2021.1944188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The barrier properties of lipid membranes are often determined by investigating their solute permeability with the help of spectroscopic methods and the use of liposome-encapsulated self-quenching fluorescent dyes, for example, Carboxyfluorescein (CF). It was shown previously that liposome-surface interactions, and thus the choice of cuvette material, influence the result of such spectroscopic permeability/leakage experiments. In this work, we explore different methods to minimize the artifacts observed in spontaneous leakage measurements performed with cholesterol-containing liposomes. The spontaneous leakage of CF from liposomes with different composition and surface properties is monitored in cuvettes composed of quartz, polystyrene (PS), and Poly(methyl methacrylate) (PMMA). Our results show that significantly different leakage profiles are recorded for the exact same liposome batch depending on the cuvette material used. Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) experiments indicate that these discrepancies likely arise from side processes occurring at the solution-cuvette interface, mainly, the attaching and spreading of liposomes. Further, we show that in some cases it is possible to minimize liposome-cuvette interactions, and reduce the experimental artifacts, by supplementing the liposomes with polyethylene glycol (PEG)-grafted lipids or gangliosides, and/or by pre-adsorbing free PEG to the cuvette walls. The collected data suggest that quartz cuvettes modified by adsorption of PEG8000 are suitable for spontaneous leakage experiments with POPC:cholesterol-based liposomes, while other cuvette materials perform poorly in the same experiments.
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Affiliation(s)
- Philipp Grad
- Department of Chemistry - Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | | | - Katarina Edwards
- Department of Chemistry - Ångström Laboratory, Uppsala University, Uppsala, Sweden
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16
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Boote AT, Bigsby RJ, Deehan DJ, Rankin KS, Swailes DC, Hyde PJ. Does vacuum mixing affect diameter shrinkage of a PMMA cement mantle during in vitro cemented acetabulum implantation? Proc Inst Mech Eng H 2020; 235:133-140. [PMID: 33054541 PMCID: PMC7841715 DOI: 10.1177/0954411920964023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Radiolucent lines on immediate postoperative cemented acetabular component radiographs between the PMMA bone cement mantle and bone are an indicator of an increased risk of early loosening. The cause of these lines has yet to be identified. Thermal and chemical necrosis, fluid interposition and cement shrinkage have all been suggested in the literature. The aim of the study reported here was to take an engineering approach - eliminating confounding variables present during surgery - to quantify the size of the interstice created by cement shrinkage when a 50 mm diameter flanged acetabular cup is implanted in a model acetabulum with a 52 mm hemispherical bore under controlled conditions using vacuum and non-vacuum mixed cement. Irrespective of the mixing method used, a significant interstice was created between the bone cement and the mock acetabulum. When the cement was mixed under vacuum the interstice created between the mock acetabulum and the cement mantle was 0.60 mm ± 0.09 mm; when the cement was mixed under non-vacuum conditions the interstice created was 0.39 mm ± 0.15 mm. Possible explanations for radiolucent lines are discussed.
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17
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Brió
Pérez M, Cirelli M, de Beer S. Degrafting of Polymer Brushes by Exposure to Humid Air. ACS APPLIED POLYMER MATERIALS 2020; 2:3039-3043. [PMID: 34124685 PMCID: PMC8192051 DOI: 10.1021/acsapm.0c00474] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 07/08/2020] [Indexed: 05/22/2023]
Abstract
It is well-known that polymer brushes can degraft in aqueous liquids. Here we show that brushes can deteriorate in humid air too. We observe that the detachment rate of the brushes increases with increasing relative humidity and hydrophilicity of the brushes. We relate this to the increase in water absorption as these parameters are increased. Our results imply that protective measures that are at present being developed for applications of brushes in liquids will also be key in enabling the long-term storage and utilization of hydrophilic brushes in air.
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Affiliation(s)
- Maria Brió
Pérez
- Materials Science and Technology of
Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Marco Cirelli
- Materials Science and Technology of
Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Sissi de Beer
- Materials Science and Technology of
Polymers, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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18
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Waldman RZ, Mandia DJ, Yanguas-Gil A, Martinson ABF, Elam JW, Darling SB. The chemical physics of sequential infiltration synthesis-A thermodynamic and kinetic perspective. J Chem Phys 2019; 151:190901. [PMID: 31757164 DOI: 10.1063/1.5128108] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Sequential infiltration synthesis (SIS) is an emerging materials growth method by which inorganic metal oxides are nucleated and grown within the free volume of polymers in association with chemical functional groups in the polymer. SIS enables the growth of novel polymer-inorganic hybrid materials, porous inorganic materials, and spatially templated nanoscale devices of relevance to a host of technological applications. Although SIS borrows from the precursors and equipment of atomic layer deposition (ALD), the chemistry and physics of SIS differ in important ways. These differences arise from the permeable three-dimensional distribution of functional groups in polymers in SIS, which contrast to the typically impermeable two-dimensional distribution of active sites on solid surfaces in ALD. In SIS, metal-organic vapor-phase precursors dissolve and diffuse into polymers and interact with these functional groups through reversible complex formation and/or irreversible chemical reactions. In this perspective, we describe the thermodynamics and kinetics of SIS and attempt to disentangle the tightly coupled physical and chemical processes that underlie this method. We discuss the various experimental, computational, and theoretical efforts that provide insight into SIS mechanisms and identify approaches that may fill out current gaps in knowledge and expand the utilization of SIS.
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Affiliation(s)
- Ruben Z Waldman
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, USA
| | - David J Mandia
- Applied Materials Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Angel Yanguas-Gil
- Applied Materials Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Alex B F Martinson
- Advanced Materials for Energy-Water Systems (AMEWS) Energy Frontier Research Center (EFRC), Lemont, Illinois 60439, USA
| | - Jeffrey W Elam
- Advanced Materials for Energy-Water Systems (AMEWS) Energy Frontier Research Center (EFRC), Lemont, Illinois 60439, USA
| | - Seth B Darling
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, USA
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19
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Seasoning Polymethyl Methacrylate (PMMA) Bone Cements with Incorrect Mix Ratio. MATERIALS 2019; 12:ma12193073. [PMID: 31547178 PMCID: PMC6804204 DOI: 10.3390/ma12193073] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/03/2019] [Accepted: 09/18/2019] [Indexed: 02/07/2023]
Abstract
Cemented joint prostheses are widely used in orthopaedic surgery; however, implants/bone bonds are known to be susceptible to aseptic loosening, particularly in the case of long-term performance. The exact mechanism of this failure is under constant examination. One of the critical factors to the final mechanical functionality of bone cement can be an incorrect mix ratio of a two-component material (powdered polymer and liquid monomer). It can result in the deterioration of the final mechanical strength properties. The paper presents the results from an experimental study on the effects of the deviation from the correct mix ratio on the moisture uptake and the compression strength of cement depending on the seasoning time in Ringer's solution. The results were subjected to statistical analysis and a mathematical model was developed.
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20
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Liu X, Shi H, Xie B, Dionysiou DD, Zhao Y. Microplastics as Both a Sink and a Source of Bisphenol A in the Marine Environment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:10188-10196. [PMID: 31393116 DOI: 10.1021/acs.est.9b02834] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microplastics were demonstrated to be an environmental sink for hydrophobic organic pollutants, while they can also serve as a potential source of such pollutants. In this study, the sorption and release of bisphenol A in marine water were investigated through laboratory experiments. Sorption and desorption isotherms were developed, and the results reveal that sorption and desorption depend on the crystallinity, elasticity, and hydrophobicity of the polymer concerned. The adsorption and partition of bisphenol A can be quantified using a dual-mode model of the sorption mechanisms. Polyamide and polyurethane were found to exhibit the highest sorption capacity for bisphenol A, and it was almost irreversible, probably due to hydrogen bonding. Polyethylenes and polypropylene exhibited high and reversible sorption without noticeable desorption hysteresis. Glassy polystyrene, poly(vinyl chloride), poly(methyl methacrylate), and poly(ethylene terephthalate) exhibited low sorption capacity and only partial reversibility. Low-density polyethylene and polycarbonate microplastic particles were for the first time proved to be a persistent source releasing bisphenol A into aquatic environments. Salinity, pH, coexisting estrogens, and water chemistry influence the sorption/desorption behaviors to different degrees. Plastic particles can serve as transportation vectors for bisphenol A, which may constitute an ecological risk.
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Affiliation(s)
| | | | | | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering (DChEE) , University of Cincinnati , 705 Engineering Research Center , Cincinnati , Ohio , United States
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21
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Liu X, Xu J, Zhao Y, Shi H, Huang CH. Hydrophobic sorption behaviors of 17β-Estradiol on environmental microplastics. CHEMOSPHERE 2019; 226:726-735. [PMID: 30959457 DOI: 10.1016/j.chemosphere.2019.03.162] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 03/12/2019] [Accepted: 03/25/2019] [Indexed: 06/09/2023]
Abstract
Microplastics (MPs) have been regarded as a vector for contaminants and greatly affect the migration and fate of hydrophobic organic compounds (HOCs) in marine water. In this study, the sorption behavior of 17β-estradiol (E2) on MPs was investigated in marine water system. The sorption capacity of E2 varied greatly with the chemical structures of MPs. The adsorption or partition contribution of E2 sorption on MPs was well quantified with adsorption-partition dual-mode model mechanism. The hydrophobic partition dominantly regulates the sorption of E2 due to the high crystallinity of MPs and high accessibility of amorphous domain of rubbery MPs. Smaller particle size benefits the sorption of E2 on same kind of MPs. The salinity and dissolved organic matter (DOM) have minor effect on E2 sorption by MPs in real marine water. The result shows that the MPs greatly influence the transportation of E2 and cause potential environmental risk to marine ecosystem.
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Affiliation(s)
- Xuemin Liu
- School of Ecological and Environmental Sciences, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, East China Normal University, Shanghai, 200241, China; Institute of Eco-Chongming, Shanghai, 200062, China
| | - Jiang Xu
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200062, China
| | - Yaping Zhao
- School of Ecological and Environmental Sciences, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, East China Normal University, Shanghai, 200241, China; Institute of Eco-Chongming, Shanghai, 200062, China.
| | - Huahong Shi
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai, 200062, China; Institute of Eco-Chongming, Shanghai, 200062, China
| | - Ching-Hua Huang
- School of Civil & Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0355, USA
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22
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Funk GA, Burkes JC, Cole KA, Rahaman MN, McIff TE. Antibiotic Elution and Mechanical Strength of PMMA Bone Cement Loaded With Borate Bioactive Glass. J Bone Jt Infect 2018; 3:187-196. [PMID: 30416942 PMCID: PMC6215993 DOI: 10.7150/jbji.27348] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 08/06/2018] [Indexed: 12/11/2022] Open
Abstract
Introduction: Local delivery of antibiotics using bone cement as the delivery vehicle is an established method of managing implant-associated orthopedic infections. Various fillers have been added to cement to increase antibiotic elution, but they often do so at the expense of strength. This study evaluated the effect of adding a borate bioactive glass, previously shown to promote bone formation, on vancomycin elution from PMMA bone cement. Methods: Five cement composites were made: three loaded with borate bioactive glass along with 0, 1, and 5 grams of vancomycin and two without any glass but with 1 and 5 grams vancomycin to serve as controls. The specimens were soaked in PBS. Eluate of vancomycin was collected every 24 hours and analyzed by HPLC. Orthopedic-relevant mechanical properties of each composite were tested over time. Results: The addition of borate bioactive glass provided an increase in vancomycin release at Day 1 and an increase in sustained vancomycin release throughout the treatment period. An 87.6% and 21.1% increase in cumulative vancomycin release was seen for both 1g and 5g loading groups, respectively. Compressive strength of all composites remained above the weight-bearing threshold of 70 MPa throughout the duration of the study with the glass-containing composites showing comparable strength to their respective controls. Conclusion: The incorporation of borate bioactive glass into commercial PMMA bone cement can significantly increase the elution of vancomycin. The mechanical strength of the cement-glass composites remained above 70 MPa even after soaking for 8 weeks, suggesting their suitability for orthopedic weight-bearing applications.
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Affiliation(s)
- Grahmm A Funk
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, KS, United States
| | - Jonathan C Burkes
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, KS, United States
| | - Kimberly A Cole
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, KS, United States
| | - Mohamed N Rahaman
- Department of Materials Science and Engineering, Missouri University of Science and Technology, Rolla, MO, United States
| | - Terence E McIff
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, KS, United States
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23
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Turgut H, Varadharajan D, Dingenouts N, Delaittre G. Nanostructured Thin Films of Moderately Functionalized PMMA-b
-PS. Macromol Rapid Commun 2018; 39:e1800231. [DOI: 10.1002/marc.201800231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 05/16/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Hatice Turgut
- Institute of Toxicology and Genetics; Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
- Macromolecular Architectures; Institute for Chemical Technology and Polymer Chemistry; Karlsruhe Institute of Technology (KIT); Engesserstr. 18 76128 Karlsruhe Germany
| | - Divya Varadharajan
- Institute of Toxicology and Genetics; Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
- Macromolecular Architectures; Institute for Chemical Technology and Polymer Chemistry; Karlsruhe Institute of Technology (KIT); Engesserstr. 18 76128 Karlsruhe Germany
| | - Nico Dingenouts
- Polymeric Materials; Institute for Chemical Technology and Polymer Chemistry; Karlsruhe Institute of Technology (KIT); Engesserstr. 18 76128 Karlsruhe Germany
| | - Guillaume Delaittre
- Institute of Toxicology and Genetics; Karlsruhe Institute of Technology (KIT); Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
- Macromolecular Architectures; Institute for Chemical Technology and Polymer Chemistry; Karlsruhe Institute of Technology (KIT); Engesserstr. 18 76128 Karlsruhe Germany
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24
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Son YJ, Chun KY, Kim JS, Lee JH, Han CS. Effects of chemical and physical defects on the humidity sensitivity of graphene surface. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.10.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Stanton ALD, Serrano KA, Braun PV, Bailey RC. Polymer Brush-Modified Microring Resonators for Partition-Enhanced Small Molecule Chemical Detection. ChemistrySelect 2017. [DOI: 10.1002/slct.201700082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Alexandria L. D. Stanton
- Department of Chemistry; University of Illinois at Urbana-Champaign; 600 S. Mathews Ave. Urbana, IL 61801
| | - Kali A. Serrano
- Department of Chemistry; University of Illinois at Urbana-Champaign; 600 S. Mathews Ave. Urbana, IL 61801
| | - Paul V. Braun
- Department of Materials Science and Engineering; University of Illinois at Urbana-Champaign; 1304 W. Green St. Urbana, IL 61801
| | - Ryan C. Bailey
- Department of Chemistry; University of Illinois at Urbana-Champaign; 600 S. Mathews Ave. Urbana, IL 61801
- Current address: Department of Chemistry; University of Michigan; 930 N. University Ave. Ann Arbor, MI 48109
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26
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Gao J, Li B, Tan J, Chow P, Lu TM, Koratkar N. Aging of Transition Metal Dichalcogenide Monolayers. ACS NANO 2016; 10:2628-35. [PMID: 26808328 DOI: 10.1021/acsnano.5b07677] [Citation(s) in RCA: 168] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Two-dimensional sheets of transition metal dichalcogenides are an emerging class of atomically thin semiconductors that are considered to be "air-stable", similar to graphene. Here we report that, contrary to current understanding, chemical vapor deposited transition metal dichalcogenide monolayers exhibit poor long-term stability in air. After room-temperature exposure to the environment for several months, monolayers of molybdenum disulfide and tungsten disulfide undergo dramatic aging effects including extensive cracking, changes in morphology, and severe quenching of the direct gap photoluminescence. X-ray photoelectron and Auger electron spectroscopy reveal that this effect is related to gradual oxidation along the grain boundaries and the adsorption of organic contaminants. These results highlight important challenges associated with the utilization of transition metal dichalcogenide monolayers in electronic and optoelectronic devices. We also demonstrate a potential solution to this problem, featuring encapsulation of the monolayer sheet by a 10-20 nm thick optically transparent polymer (parylene C). This strategy is shown to successfully prevent the degradation of the monolayer material under accelerated aging (i.e., high-temperature, oxygen-rich) conditions.
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Affiliation(s)
- Jian Gao
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Baichang Li
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Jiawei Tan
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Phil Chow
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Toh-Ming Lu
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
| | - Nikhil Koratkar
- Materials Science and Engineering, ‡Physics, Applied Physics, and Astronomy, and §Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute , Troy, New York 12180, United States
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27
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Cheng HL, Lin JW, Ruan J, Lin CH, Wu FC, Chou WY, Chen CH, Chang CK, Sheu HS. Spontaneous Formation of an Ideal-Like Field-Effect Channel for Decay-Free Polymeric Thin-Film Transistors by Multiple-Scale Phase Separation. ACS APPLIED MATERIALS & INTERFACES 2015; 7:16486-16494. [PMID: 26177076 DOI: 10.1021/acsami.5b03864] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate semiconducting polymer-based thin-film transistors (PTFTs) with fast switching performance and an uncommon nondecaying feature. These PTFTs based on widely studied poly(3-hexylthiophene) are developed by incorporating the insulating polymer into the active channel and subjecting the compound to specific, spontaneous multiple-scale phase separation (MSPS). An in-depth study is conducted on the interfacial and phase-separated microstructure of the semiconducting/insulating blending active layer and its effect on the electrical characteristics of PTFTs. The polyblends exhibit a confined crystallization behavior with continuously semiconducting crystalline domains between scattered insulator-rich domains. The insulator-rich domains can block leakage current and strengthen the gate control of the channel. A small amount of the insulating polymer penetrates the bottom of the active channel, resulting in effective interface modification. We show specific MSPS morphology of the present blending films to reduce charge trapping effects, enhance charge accumulation, and create a high-seed switching channel. The findings enable us to develop the required morphological conceptual model of the ideal-like field-effect-modulated polymer-based active channel. The polyblend-based PTFTs with MSPS morphology also have promising sensing functions. This study offers an effective approach for overcoming the major drawbacks (instability and poor switching) of PTFTs, thus allowing such transistors to have potential applications.
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Affiliation(s)
- Horng-Long Cheng
- †Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Jr-Wei Lin
- †Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Jrjeng Ruan
- ‡Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Chia-Hsien Lin
- †Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Fu-Chiao Wu
- †Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Wei-Yang Chou
- †Department of Photonics, Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan 701, Taiwan
| | - Ching-Hsiang Chen
- §Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei, 106, Taiwan
- ∥Protrustech Corporation Limited, Tainan, Taiwan
| | - Chung-Kai Chang
- ⊥National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
| | - Hwo-Shuenn Sheu
- ⊥National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan
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Gao S, Gao S, Xu B, Yu H. Effects of Different pH-Values on the Nanomechanical Surface Properties of PEEK and CFR-PEEK Compared to Dental Resin-Based Materials. MATERIALS 2015; 8:4751-4767. [PMID: 28793469 PMCID: PMC5455519 DOI: 10.3390/ma8084751] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/13/2015] [Accepted: 07/22/2015] [Indexed: 02/05/2023]
Abstract
The study determines the stability and durability of polyetheretherketone (PEEK) and a carbon fiber-reinforced PEEK (CFR-PEEK) with 30% short carbon fibers, a dental composite based on Bis-GMA and polymethylmethacrylate (PMMA) under the influence of different pH-values of the oral environment in vitro. Nanomechanical properties were investigated by nanoindentation and nanoscratch tests before and after incubation of the specimens at 37 °C for 30 days in artificial saliva with pH-values of 3, 7 and 10, respectively. Nanoindentation and nanoscratching tests were performed using the Hysitron TI950 TriboIndenter to evaluate the reduced elastic moduli, nanohardness, viscoelasticity, friction coefficient and residual scratch profiles. After treatment, the nanomechanical properties of unfilled PEEK did not change. The reduced elastic moduli and nanohardness of the carbon fiber-reinforced PEEK increased significantly. The reduced elastic moduli and nanohardness of CHARISMA decreased. The plasticity of all materials except that of the unfilled PEEK increased. This indicates that different pH-values of the artificial saliva solutions had no obvious influences on the nanomechanical properties of the PEEK matrix. Therefore, the aging resistance of the unfilled PEEK was higher than those of other materials. It can be deduced that the PEEK matrix without filler was more stable than with filler in the nanoscale.
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Affiliation(s)
- Shuai Gao
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, NO. 14, 3rd Section of Ren Min Nan Road, Chengdu 610041, China.
| | - Shanshan Gao
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, NO. 14, 3rd Section of Ren Min Nan Road, Chengdu 610041, China.
| | - Baohua Xu
- China-Japan Friendship Hospital, Yinghua Road, Chaoyang District, Beijing 100020, China.
| | - Haiyang Yu
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, NO. 14, 3rd Section of Ren Min Nan Road, Chengdu 610041, China.
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Mochizuki A, Namiki T, Nishimori Y, Ogawa H. Study of the water structure in poly(methyl methacrylate-block-2-hydroxyethyl methacrylate) and its relationship to platelet adhesion on the copolymer surface. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2015; 26:750-65. [DOI: 10.1080/09205063.2015.1056457] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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30
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Reifler FA, Hufenus R, Krehel M, Zgraggen E, Rossi RM, Scherer LJ. Polymer optical fibers for textile applications – Bicomponent melt spinning from cyclic olefin polymer and structural characteristics revealed by wide angle X-ray diffraction. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.08.071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Feng S, Chen Y, Mai B, Wei W, Zheng C, Wu Q, Liang G, Gao H, Zhu F. Glass transition of poly(methyl methacrylate) nanospheres in aqueous dispersion. Phys Chem Chem Phys 2014; 16:15941-7. [DOI: 10.1039/c4cp01849d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Ageing and moisture uptake in polymethyl methacrylate (PMMA) bone cements. J Mech Behav Biomed Mater 2013; 32:76-88. [PMID: 24445003 PMCID: PMC3988952 DOI: 10.1016/j.jmbbm.2013.12.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 12/08/2013] [Accepted: 12/10/2013] [Indexed: 11/24/2022]
Abstract
Bone cements are extensively employed in orthopaedics for joint arthroplasty, however implant failure in the form of aseptic loosening is known to occur after long-term use. The exact mechanism causing this is not well understood, however it is thought to arise from a combination of fatigue and chemical degradation resulting from the hostile in vivo environment. In this study, two commercial bone cements were aged in an isotonic fluid at physiological temperatures and changes in moisture uptake, microstructure and mechanical and fatigue properties were studied. Initial penetration of water into the cement followed Fickian diffusion and was thought to be caused by vacancies created by leaching monomer. An increase in weight of approximately 2% was experienced after 30 days ageing and was accompanied by hydrolysis of poly(methyl methacrylate) (PMMA) in the outermost layers of the cement. This molecular change and the plasticising effect of water resulted in reduced mechanical and fatigue properties over time. Cement ageing is therefore thought to be a key contributor in the long-term failure of cemented joint replacements. The results from this study have highlighted the need to develop cements capable of withstanding long-term degradation and for more accurate test methods, which fully account for physiological ageing. Two commercial bone cements were aged in Ringer's solution at 37 °C for 60 days. Moisture uptake, mechanical, fatigue and microstructural properties were studied. A maximum of 2% change in weight occurred due to Fickian diffusion after 30 days. Hydrolysis of PMMA and reduced mechanical and fatigue properties were observed. Cement degradation is thought to contribute to the failure of cemented implants.
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Pascaretti-Grizon F, Mabilleau G, Chappard D. Abrasion of 6 dentifrices measured by vertical scanning interference microscopy. J Appl Oral Sci 2013; 21:475-81. [PMID: 24212995 PMCID: PMC3881835 DOI: 10.1590/1679-775720130204] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 08/12/2013] [Indexed: 11/22/2022] Open
Abstract
Objectives The abrasion of dentifrices is well recognized to eliminate the dental plaque. The
aims of this study were to characterize the abrasive powders of 6 dentifrices (3
toothpastes and 3 toothpowders) and to measure the abrasion on a test surface by
Vertical Scanning Interference microscopy (VSI). Material and Methods Bright field and polarization microscopy were used to identify the abrasive
particles on the crude dentifrices and after prolonged washes. Scanning electron
microscopy and microanalysis characterized the shape and nature of the particles.
Standardized and polished blocks of poly(methylmethacrylate) were brushed with a
commercial electric toothbrush with the dentifrices. VSI quantified the mean
roughness (Ra) and illustrated in 3D the abraded areas. Results Toothpastes induced a limited abrasion. Toothpowders induced a significantly
higher roughness linked to the size of the abrasive particles. One powder
(Gencix® produced a high abrasion when used with a standard testing
weight. However, the powder is based on pumice particles covered by a plant
homogenate that readily dissolves in water. When used in the same volume, or after
dispersion in water, Ra was markedly reduced. Conclusion Light and electron microscopy characterize the abrasive particles and VSI is a new
tool allowing the analysis of large surface of abraded materials.
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Bog U, Laue T, Grossmann T, Beck T, Wienhold T, Richter B, Hirtz M, Fuchs H, Kalt H, Mappes T. On-chip microlasers for biomolecular detection via highly localized deposition of a multifunctional phospholipid ink. LAB ON A CHIP 2013; 13:2701-7. [PMID: 23649356 DOI: 10.1039/c3lc50149c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We report on a novel approach to realize on-chip microlasers, by applying highly localized and material-saving surface functionalization of passive photonic whispering gallery mode microresonators. We apply dip-pen nanolithography on a true three-dimensional structure. We coat solely the light-guiding circumference of pre-fabricated poly(methyl methacrylate) resonators with a multifunctional molecular ink. The functionalization is performed in one single fabrication step and simultaneously provides optical gain as well as molecular binding selectivity. This allows for a direct and flexible realization of on-chip microlasers, which can be utilized as biosensors in optofluidic lab-on-a-chip applications. In a proof-of-concept we show how this highly localized molecule deposition suffices for low-threshold lasing in air and water, and demonstrate the capability of the ink-lasers as biosensors in a biotin-streptavidin binding experiment.
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Affiliation(s)
- Uwe Bog
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76128 Karlsruhe, Germany.
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