Surface modification and property analysis of biomedical polymers used for tissue engineering

Event Abstract Back to Event Biomedical coatings prepared by magnetron sputtering Sandra Rodil1, Phaedra Silva-Bermudez2, Argelia Almaguer-Flores3 and Rene Olivares-Navarrete4 1 Universidad Nacional Autónoma de México, Instituto de Investigaciones en Materiales, Mexico 2 Instituto Nacional de Rehabilitación, Terapia Celular y Medicina Regenerativa, Mexico 3 Universidad Nacional Autónoma de México, Facultad de Odontología, Mexico 4 Virginia Commonwealth University, 2Department of Biomedical Engineering, United States Introduction: Nowadays, it is generally accepted that surfaces are critically important to determine the degree of tissue interaction between an implanted device and the host. Thus, much more importance has been given to study and modify the biomaterial surfaces to improve biocompatibility, cell adhesion, proliferation and differentiation. During the last years the research has evolved from the improvement of bulk properties and design of the implants to the development of a variety of bio-functional surface modifications, such as surface topography at both micro and nanoscale, adhesion of growth factors or coating deposition. The use of coatings allows the synthesis of hybrid materials, in which surface and bulk properties are de-coupled, so different functionalities (biocompatibility, antibacterial, etc...) could be obtained using the same substrate material. Materials: Metal oxide coatings (TiOx, ZrOx, TaOx and NbOx). Methods: The deposition of the coatings was done by reactive magnetron sputtering on stainless steel or titanium substrates. The coatings structure, composition and surface properties were measured. Electrochemical characterization using different electrolytes that simulate the biological fluids were used to evaluate the corrosion resistance provided by the coatings and the effect of the electrolyte composition on the response. The biological-surface interactions were also evaluated by studying protein-surface (adsorption), bacteria-surface (adhesion and biofilm formation) and cell-surface (adhesion, proliferation and differentiation) interactions. Discussion: The paper will presented a summary of the biological response from the four oxide coatings and the correlation between such response and the surface properties, including the effect of crystallinity or nanoroughness. One important factor to analyze is the fact that by using sputtered deposited coatings, it is possible to evaluate separately the effect of the surface chemical composition and the roughness, not so easily achieved when bulk materials are used. Conclusions: The in vitro results obtained from the different oxide coatings suggested that by using deposition methods, it is possible to create biomedical coatings that mimic the cellular response of the Ti-optimized metallic implants, with the advantage that such coatings could be deposited on hard-polymers or ceramics. UNAM PAPIIT Keywords: corrosion, Surface modification, surface property, Cell response Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Composites: polymeric, ceramic and metallic Citation: Rodil S, Silva-Bermudez P, Almaguer-Flores A and Olivares-Navarrete R (2016). Biomedical coatings prepared by magnetron sputtering. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.01672 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Sandra Rodil Phaedra Silva-Bermudez Argelia Almaguer-Flores Rene Olivares-Navarrete Google Sandra Rodil Phaedra Silva-Bermudez Argelia Almaguer-Flores Rene Olivares-Navarrete Google Scholar Sandra Rodil Phaedra Silva-Bermudez Argelia Almaguer-Flores Rene Olivares-Navarrete PubMed Sandra Rodil Phaedra Silva-Bermudez Argelia Almaguer-Flores Rene Olivares-Navarrete Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

In the biomaterial field, the modification of surfaces are used to create polymers with high performances, preserving their bulk properties and creating specific interactions between the designed surfaces and the cells or tissues. The polymers were irradiated with a 900 keV Helium beam to modify their surface properties. Cell cultivation on the samples was done using human osteoblasts cells (hFOB 1.19). For PTFE, PS and PEEK polymers, the cell adhesion occurs after reached some threshold values of fluences. For PET or PMMA polymers, the cells adhere on the non irradiated samples, however the fluence value modifies the cell density. For PMMA and PTFE both, the fluence and the current density influence the cell adhesion. By modifying the appropriate parameters on each material, the control of the cell adhesion is possible. Indeed the surface treatment must be selected and adapted according to the further application: for biosensors, tissue engineering, tissue regeneration, neural probes, drug delivery, bio‐actuators etc.

Correlation between surface properties and catalytic activity of clay catalysts

Surface engineered poly(dimethylsiloxane)/carbon nanotube nanocomposite pad as a flexible platform for chemical sensors

This special issue contains selected papers which were presented as invited and contributed communications at the workshop entitled ‘Surface modification and functionalization of materials for biomedical applications’ (BIO-COAT 2010) which was held on 24 June 2010 in Zaragoza (Spain). The surface of a material plays a major role in its interaction with the biological medium. Processes related to the mechanical stability of articular devices in contact, osseointegration, thrombogenicity, corrosion and leaching, or the inflammatory response of rejection of a material, are clearly conditioned by the surface properties. Therefore, the modification or functionalization of surfaces can have an important impact on these issues. New techniques for functionalization by thin film deposition or surface treatments help to improve superficial properties, while understanding the interaction of the surface–biological medium is critical for their application in new devices. Jointly organized by the Spanish Materials Research Society, BIO-COAT 2010 provided an open forum to discuss the progress and latest developments in thin film processing and the engineering of biomaterials. Invited lectures were particularly aimed at providing overviews on scientific topics and were given by recognized world-class scientists. Two of them have contributed with a proceedings article to this selected collection (articles 012001 and 012008). The contributed communications were focused on particular cutting-edge aspects of thin film science and functionalization technologies for biomaterials, showing the major scientific push of Spanish research groups in the field. The 2010 BIO-COAT conference was organized along four main topics: (1) functionalization and texture on surfaces, (2) tribology and corrosion, (3) the surface modification of biomaterials, and (4) surface–biological environment interactions. The papers published in this volume were accepted for publication after peer-review as are regular papers. The editor of this proceedings volume gratefully acknowledges all referees for their valuable work, sometimes working to quite short deadlines. Finally, BIO-COAT 2010 would not have been successful without the strong involvement and input of the local organizing committee in Zaragoza, and the support of the University of Zaragoza. We sincerely thank them all for their efforts. Jose L Endrino (Editor) Jose A Puértolas (Chairman) Jose M Albella (Chairman)

Bulk metallic glasses (BMGs) are well known for their promising properties. Surface properties can be further improved by using certain techniques such as electron beam melting (EBM), laser beam melting (LBM), ion irradiation, ion implantation and neutron irradiation. BMGs especially Zr-based BMGs have numerous applications as structural materials. In this manuscript, the results are presented on microstructural investigations and phase formations in Zr-based BMGs modified by using above mentioned techniques. Microstructure was studied by scanning electron microscopy (SEM). Phase analysis was done by X-ray diffraction (XRD) and confirmed by energy dispersive spectroscopy (EDS). Vickers hardness was measured and correlated with the microstructure. The phases identified in Zr-Cu-Al-Ni alloy samples modified by EBM, LBM and ion irradiation are Ni-Zr, NiZr2, CuZr2, Cu10Zr7 and Al2NiZr6. ZrSi2 phase was detected in Zr55Cu30Al10Ni5 and Zr65Cu17Ni10Al8 BMGs irradiated with Si+ (ions). About 20-35 % increase in hardness and elastic moduli was achieved by surface modification. Modifications of BMGs by electron and laser beams melted the materials surfaces while ion irradiation improved the mechanical properties of localized zones without melting.

The hydrophobic materials were treated by plasma continual treater to achieve its surface modification and improve its wettability. The influences of treating time, discharge power, working gases and gas pressure on the surface modification of the materials have been investigated. The chemical states and species on the surface of materials have been investigated by some technologies such as contact angles. After plasma surface treatment, the contact angles of PTFE sharply decrease, and the alkali liquid absorption of PE increased to three times of its weight. The contact angles of silicon rubber and polyester decreased remarkably after surface modification. PTFE films were grafted with crylic acid to evaluate the ageing. The effect of vacuum ultraviolet radiation to surface modification was initially described. The results of experiment demonstrate that the better wettability of hydrophobic material can be achieved. The technique and the equipment have the promotional value for industrial application.

Optical Bioimaging and Therapy

Polymeric membranes have emerged as a competitive technology in gas separation processes due to their notable energy efficiency, environmentally friendly attributes and minimal system footprint. To enhance the performance of conventional polymeric membranes, significant research efforts have been dedicated to modifying their surface properties in the last decade. Among the various techniques explored, membrane surface modification using coating methods, such as dip-coating, spray-coating, grafting and interfacial polymerization stands out as one of the most popular and straightforward approaches. Scientists have utilized a diverse array of coating solutions comprising either polymeric materials or hybrid materials in these methods, yielding promising outcomes. This article aims to present a comprehensive review of the advancements made in surface coating approaches employed for modifying hollow fiber membrane surfaces over the past decade. The review encompasses an evaluation of how different coating approaches and solutions affect the surface's physicochemical properties and the gas separation performance of the membranes. Furthermore, the article delves into discussing technical challenges associated with these surface coating approaches, providing an insightful analysis. Lastly, the review concludes by outlining perspectives and recommending future research directions for this area of study, highlighting the potential avenues for innovation and advancement in surface-coated hollow fiber membranes for gas separation applications.

Surface engineering of porous carbons for next-generation supercapacitors

The COVID-19 pandemic has demonstrated that hygiene habits reduce the spread of the SARS-CoV-2 virus on contaminated surfaces. In this context, compounds with biocidal properties can act as surface coatings, especially in hospital environments, a source of pathogenic microorganisms. Therefore, the purpose of this review was to report an overview of recent studies with biocidal agents, focusing on polymeric surface modification. Methods such as direct incorporation, direct deposition, and chemical deposition of the microbial agent on the polymeric surface and surface modification without a microbial agent were discussed. Despite several studies in the literature, antimicrobial materials still face challenges such as commercialization, material stability in post-processing, and guarantee of long cycles. Moreover, effectiveness, toxicity, and final cost must be balanced. We also discussed the concept of antiviral activity and the action mode of the materials. Inorganic, organic materials, nanocomposites, and biopolymers have been addressed as viral inhibitors of several diseases. Lastly, we explored the functional validation of polymeric surface through characterization techniques.

Cellulose Nanocrystals (CNCs) have been touted to be among the materials of the 21st century. It is an emerging biocompatible and biodegradable nanomaterial with unique physicochemical properties adaptable to various surface modifications. The characteristics and properties of CNCs are now understood to depend upon the source of the cellulose and the conditions of its isolation. Over the past decade, CNCs with various morphologies, including rod, ribbon, needle shapes, spherical, square, block and rectangular shapes with unique surface properties, have been synthesized. Studies have shown that surface and morphological properties of CNCs have substantial control over the rheology, cytotoxicity and cellular uptake, which ultimately influence its purposive biomedical applications. The objective of the current survey is to analyze the advances made in the shape-controlled synthesis and fabrication of CNCs morphology and review the influence such morphological variations have on its functionality in biomedical fields.

Influence of Zr addition in β Ti-25Ta-xZr alloys on oxide formation by MAO-treatment

The modification of surfaces by the deposition of a robust overlayer provides an excellent handle with which to tune the properties of a bulk substrate to those of interest. Such control over the surface properties becomes increasingly important with the continuing efforts at down-sizing the active components in optoelectronic devices, and the corresponding increase in the surface area/volume ratio. Relevant properties to tune include the degree to which a surface is wetted by water or oil. Analogously, for biosensing applications there is an increasing interest in so-called "romantic surfaces": surfaces that repel all biological entities, apart from one, to which it binds strongly. Such systems require both long lasting and highly specific tuning of the surface properties. This Review presents one approach to obtain robust surface modifications of the surface of oxides, namely the covalent attachment of monolayers.

The surface properties and electrical behavior of carbon-based materials can be effectively modified by energetic ion irradiation. In the present study, graphene oxide (GO) and cyclic olefin copolymer foils (COC, Topas 112 and 011, respectively) were irradiated with 1 MeV Au ions using a 3 MV Tandetron accelerator at fluences of 1 × 1014, 1 × 1015, and 2.5 × 1015 cm-2. The irradiation induced systematic modifications in surface chemistry, morphology, wettability, and electrical properties. Composition changes were investigated using Rutherford backscattering spectrometry (RBS) and elastic recoil detection analysis (ERDA), while surface morphology and roughness were characterized by atomic force microscopy (AFM). This revealed a clear fluence-dependent evolution of nanoscale topography. The vibrational characteristics were assessed through Raman spectroscopy, and the chemical composition of the surface layers was analyzed by X-ray photoelectron spectroscopy (XPS). The surface wettability was evaluated by static contact angle measurements, and surface free energy was determined using the Owens-Wendt-Rabel-Kaelble (OWRK) method. These measurements showed a consistent decrease in water contact angle and an increase in surface free energy with increasing ion fluence in the COC substrates, whereas GO exhibited a distinct response. Electrical characterization demonstrated a pronounced fluence-dependent decrease in sheet resistivity in polymers. The results show that 1 MeV Au ion irradiation enables systematic and fluence-dependent modification of both surface and electrical properties.