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Coatings with tunable multifunctional features are important for several technological applications. Ti-based materials have been used in diverse applications ranging from metallic diodes in electronic devices up to medical implants. This work uses ab initio calculations to achieve a more fundamental understanding of the structural and electronic properties of β-TiNb and its passive TiO2 film surfaces upon Ag addition, investigating the alterations in the electronic band gap and the stability of the antibacterial coating. We find that Ag's 4d electrons introduce localized electron states, characterized by bonding features with the favoured Ti first neighbour atoms, approximately −5 eV below the fermi level in both β-TiNb bulk and surface. Ag's binding energy on β-TiNb(110) depends on the local environment (the lattice site and the type of bonded surface atoms) ranging from −2.70 eV up to −4.21 eV for the adatom on a four-fold Ti site, offering a variety of options for the design of a stable coating or for Ag ion release. In Ti–O terminated anatase and rutile (001) surfaces, surface states are introduced altering the TiO2 band gap. Silver is bonded more strongly, and therefore creates a more stable antibacterial coat on rutile than on anatase. In addition, the Ag coating exhibits enhanced 4d electron states at the highest occupied state on anatase (001),which are extended from −5 eV up to the Fermi level on rutile (001), which might be altered depending on the coat structural features, thus creating systems with tunable electronic band gap that can be used for the design of thin film semiconductors. [ABSTRACT FROM AUTHOR]

Controlling cell adhesion, viability, and proliferation on solid surfaces is critical for the successful implantation and proper functioning of temporary and permanent medical devices. While, with temporary or removable implants as well as surgical instruments, even slight cellular adhesion leads to an increased risk of secondary infections, bleeding and other complications, good cellular adhesion and viability are essential for the rapid healing and successful integration of permanent implants. This work was motivated by the growing interest in the construction of biocompatible and biodegradable coatings for the biofunctionalization of medical devices. Polysaccharide-based coatings are well known for their biocompatibility, but they are non-cell-adhesive, which hinders their application as implant coatings. In this study, we demonstrate that the incorporation of one or more graphene oxide layers in hyaluronic acid/chitosan multilayers is one avenue to regulate the degree of unspecific adhesion and growth of different cells (human umbilical vein endothelial cells, HUVEC, and mouse embryonic fibroblasts, 3T3). Furthermore, we demonstrate that this approach allows cell adhesion to be regulated across the entire range between completely prevented and highly promoted cell adhesion without introducing systemic cytotoxicity. These findings may contribute to the establishment of a new approach to adapt medical devices to cells and tissues. [ABSTRACT FROM AUTHOR]

This study investigates the in vitro biocompatibility, corrosion resistance, and adhesion strength of a gas abrasive-treated Ti6Al4V alloy, alongside microplasma-sprayed titanium and tantalum coatings. Employing a novel approach in selecting microplasma spray parameters, this study successfully engineers coatings with tailored porosity, roughness, and over 20% porosity with pore sizes up to 200 μm, aiming to enhance bone in-growth and implant integration. This study introduces an innovative methodology for quantifying surface roughness using laser electron microscopy and scanning electron microscopy, facilitating detailed morphological analysis of both the substrate and coatings. Extensive evaluations, including tests for in vitro biocompatibility, corrosion resistance, and adhesive strength, revealed that all three materials are biocompatible, with tantalum coatings exhibiting superior cell proliferation and osteogenic differentiation, as well as the highest corrosion resistance. Titanium coatings followed closely, demonstrating favorable osteogenic properties and enhanced roughness, which is crucial for cell behavior and attachment. These coatings also displayed superior tensile adhesive strengths (27.6 ± 0.9 MPa for Ti and 28.0 ± 4.9 MPa for Ta), surpassing the ISO 13179-1 standard and indicating a robust bond with the substrate. Our findings offer significant advancements in biomaterials for medical implants, introducing microplasma spraying as a versatile tool for customizing implant coatings, particularly emphasizing the superior performance of tantalum coatings in terms of biocompatibility, osteogenic potential, and corrosion resistance. This suggests that tantalum coatings are a promising alternative for enhancing the performance of metal implants, especially in applications demanding high biocompatibility and corrosion resistance. [ABSTRACT FROM AUTHOR]

Titanium is considered to be the most essential metal in the field of implantology. The main factors determining metal biocompatibility, among others, include the morphology and chemical composition of the titanium surface. Therefore, the aim of this work was to develop approaches to control the biological activity of the titanium surface by creating coatings that combine both an inorganic phase with a given morphology and organic molecules containing an integrin-selective peptide that regulate cell adhesion and proliferation. As such, we synthesized new c(RGDfC) derivatives of amino acid bisphosphonates (four examples) with different bisphosphonate anchors and maleimide linkers. These molecules were deposited on a highly developed porous surface obtained via the plasma electrolytic oxidation (PEO) of coarse-grained and nanostructured titanium. In vitro studies demonstrated the increase in the viability degree of mesenchymal stem cells and fibroblasts on the surface of coarse-grained or nanostructured titanium modified with PEO and a c(RGDfC) derivative of ε-aminocaproic acid bisphophonate with an SMCC linker. As a result, the use of conjugates of amino acid bisphosphonates with a cyclic RGD peptide for the modification of PEO-coated titanium opens the ways for the effective control of the biological activity of the metal implant surface. [ABSTRACT FROM AUTHOR]

Recently, polyether ether ketone has raised increasing interest in research and industry as an alternative material for bone implants. This polymer also has some shortcomings, as it is bioinert and its surface is relatively hydrophobic, causing poor cell adhesion and therefore slow integration with bone tissue. In order to improve biocompatibility, the surface of polyether ether ketone-based implants should be modified. Therefore, polished disc-shaped polyether ether ketone samples were surface-modified by direct current magnetron sputtering with ultrathin titanium and zirconium coatings (thickness < 100 nm). The investigation results show a uniform distribution of both types of coatings on the sample surfaces, where the coatings mostly consist of titanium dioxide and zirconium dioxide. Differential scanning calorimetry revealed that the crystalline structure of the polyether ether ketone substrates was not changed by the coating deposition. Both coatings are amorphous, as shown by X-ray diffraction investigations. The roughness of both coating types increases with increasing coating thickness, which is beneficial for cell colonization. The coatings presented and investigated in this study improve wettability, increasing surface energies, in particular the polar component of the surface energies, which, in turn, are important for cell adhesion. [ABSTRACT FROM AUTHOR]

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of intermediate ion cleaning of the Ti target on the structure and properties of the polymer fiber scaffold made by electrospinning from poly-L-lactic acid (PLLA) was investigated during deposition of Ti-N-containing coatings by DC reactive magnetron sputtering of the Ti target in a nitrogen atmosphere. SEM investigation shows that the selected plasma treatment modes can modify fiber PLLA scaffolds without changing their morphological properties. Energy-dispersive spectroscopy showed that the Ti concentration on the surface of PLLA scaffolds is increased under intermediate ion cleaning of the target, although ion cleaning did not affect the Ti distribution across the scaffold cross section. Using optical goniometry, it was found that scaffold surface treatment allows changing the contact properties of the surface from hydrophobic to hydrophilic. [ABSTRACT FROM AUTHOR]

The primary objective of this review article is to strategically screen and highlight the advancements in the area of solid phase microextraction (SPME). The plenty of review articles have been written on different aspects of SPME, this review is dedicated to provide the brief but clear overview of the research footprints so produced from SPME. Some of the key advancements in types and designs, coating materials, coating strategies, in vivo sampling and direct coupling of SPME with MS have been critically discussed. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By means of scanning electron microscopy, atomic-force microscopy, X-ray fluorescence analysis, and X-ray spectral microanalysis it was shown that, under plasma-electrolytic oxidation (PEO) of titanium alloys in pyrophosphate electrolytes, well-adhered oxide coatings with microglobular morphology result. It was demonstrated that the chemical and phase composition of the coatings, as well as the surface topography and grain size, can be controlled by changing the concentration of a pyrophosphate electrolyte and a PEO current density. It was established that the resulting oxide layer is highly resistant to abrasive wear and enhances the titanium corrosion resistance in model media (Ringer’s solution) substantially, which suggests that the coatings are promising for use in biological applications. [ABSTRACT FROM AUTHOR]

Iron‐oxide nanoparticles (IONPs) have been widely favoured due to their biodegradable, low cytotoxic effects and having reactive surface which can be altered with biocompatible coatings. Considering various medical applications of IONPs, the authors were encouraged to study whether IONPs could be effective against fungal infections caused by Candida species. In this study, IONPs were characterised by scanning electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy and vibrating sample magnetometer. The goal of this study was to evaluate the antifungal activity of IONPs against different Candida spp. compared with fluconazole (FLC). IONPs were spherical with the size of 30–40 nm. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of IONPs ranged from 62.5 to 500 µg/ml and 500 to 1000 μg/ml, respectively. The MIC and MFC of FLC were in range of 16–128 μg/ml and 64–512 μg/ml, respectively. The growth inhibition value indicated that Candida tropicalis, Candida albicans and Candida glabrata spp. were most susceptible to IONPs. The finding showed that the IONPs possessed antifungal potential against pathogenic Candida spp. and could inhibit the growth of all the tested Candida spp. Further studies, both in vitro and in vivo (including susceptibility, toxicity, Probability of kill (PK) and efficacy studies) are needed to determine whether IONPs are suitable for medicinal purposes. [ABSTRACT FROM AUTHOR]

The aim of the present article is to investigate the corrosion resistance of the Zr-Ti-Si-O coatings (as-deposited and annealed) as possible candidate as new biocompatible material. The coatings have been characterized in terms of elemental and phase composition, roughness and corrosion resistance in simulated body fluid (SBF) at 37 °C. The coatings, with a compositional ratio O/(Zr + Ti + Si) of 1.38, were found to consist of a mixture of ZrTiO4, ZrSiO4, Ti2O3, and SiOx phases. The samples annealed in O2 atmosphere at 1100 °C for 30 min resulted in improved crystallinity, increased surface area, surface roughness, and skewness. The results of the electrochemical tests revealed that Zr-Ti-Si-O coatings had improved the corrosion resistance to the aggressive attack of the SBF as compared to the bare Ti6Al4V alloy, the best results being obtained on annealed coatings. [ABSTRACT FROM AUTHOR]

Copyright of Romanian Journal of Materials / Revista Romana de Materiale is the property of Foundation for Materials Science & Engineering Serban Solacolu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The possibility of applying the extraction-pyrolysis method combined with the plasma electrolytic oxidation method in fabrication of layers with required chemical composition and properties on various materials has been investigated. The coatings have good prospects for improving the corrosion resistance, chemical inertness, and biocompatibility of materials. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to compare the biocompatibility of a new Senko E-Ternal coating (SEC) for cardiopulmonary bypass (CPB) circuits with the well-established poly-2-methoxyethyl acrylate (PMEA) coating. Methods: Forty patients undergoing aortic valve replacement were randomly assigned to either an SEC-coated group (n = 20) or a PMEA-coated group (n = 20). Clinical data and the following markers were analyzed: platelet count, platelet factor (PF) 4, fibrinogen, fibrinogen degradation products (FDPs), antithrombin III (AT III), thrombin-antithrombin complex (TAT), plasminogen, complement hemolytic activity (CH50), complement 3 (C3) and interleukin-6 (IL-6). Blood samples were obtained at five time points in both groups. Results: CPB time, aortic cross-clamp time and blood loss and transfusion were similar in both groups. There were no significant differences between the groups in terms of platelet count, PF4 and all coagulation and fibrinolytic parameters (FDP, AT III, TAT, and plasminogen) at any time points. Inflammatory markers (CH50, C3 and IL-6) were also similar in both groups at all time points. Conclusions: The SEC-coated circuit demonstrated equivalent biocompatibility to the PMEA-coated circuit. SEC-coated circuits are, therefore, favorably comparable to PMEA-coated circuits for clinical use in CPB. [ABSTRACT FROM AUTHOR]

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemistry, Physics & Technology of Surface / Khimiya, Fizyka ta Tekhnologiya Poverhni is the property of National Academy of Sciences of Ukraine, Chuiko Institute of Surface Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The motivation for these experiments was to investigate the amount and type of protein adsorption on surfaces that can be used as protective coatings on membrane based in vivo devices. Adsorption of proteins to a selection of biocompatible coatings (titanium oxide, diamond-like carbon, parylene C) and typical construction materials for Micro Electro Mechanical Systems (silicon, silicon nitride), were investigated during in vitro tests. The samples were incubated in human liver extract and bovine serum albumin (BSA) for up to 12 hours. The amount of protein adsorption was found to be low for all surfaces. Measurements of bound Iodine-125 labeled BSA, showed a protein adsorption of up to 0.2 µg BSA/cm². The specific proteins adsorbed to the surfaces after incubation in human liver extract were identified using mass spectrometry. Most of the identified adsorbed proteins were intracellular, but plasma proteins like Immunoglobulin (Ig) and serum albumin as well as hemoglobin were also identified. [ABSTRACT FROM AUTHOR]

Methods of obtaining nanostructured biocompatible coatings on medical implants are considered. The primary focus is on physical bases of formation of nanostructured coatings by different methods of plasma spraying of ceramic powders consisting of agglomerates of large and small particles after agglomeration of the powder and subsequent milling. The possibility is demonstrated of nanostructuring plasma-sprayed coatings by introducing nanoparticles into their porous structure by direct impregnation of the coatings or of the particles themselves before spraying. [ABSTRACT FROM AUTHOR]

Attenuated inflammatory response and decreased platelet activation have been claimed repeatedly when biocompatible circuits are used for cardiopulmonary bypass. We evaluated five Health Canada approved biocompatible circuit coatings (BCC) against an un-coated control group to determine their effectiveness in improving post-operative outcomes. Patients were assigned to the Control group or one of the 5 coated circuit groups: 40 Control; 33 Trillium; 32 Phisio; 34 Bioline; 33 X; and 11 GBS. Measured outcomes included: ventilator time; ICU time; post-operative chest tube drainage and transfusion volume; high sensitivity C-reactive protein (hsCRP); tau protein; and pre- and 72-hour post-operative anti-saccadic eye movement test comparisons. Results: 183 patients were enlisted into the study. One arm of the study (GBS) was abandoned after 11 patients on account of inconsistent pressure excursions within the oxygenator and the excessive consumption of platelets necessitating transfusion. Patients in the X-coated group had significantly longer ventilator and intensive care unit (ICU) time compared to the three remaining coated circuit study groups. Though not significant, patients in the X group also demonstrated the highest post-operative chest tube losses, the most platelet transfusions, the highest tau protein levels and the lowest post-operative anti-saccadic eye movement test (ASEMT) results compared to the three remaining coated groups. The patients in the Trillium, Bioline and Phisio groups showed an improvement in ventilator and ICU time relative to the Control group. The diabetic patients in the Trillium, Bioline and Phisio groups showed an improvement in bleeding relative to the diabetic patients in the Control group. Conclusion: We compared all 5 coated circuits approved for clinical use in Canada against an uncoated control circuit. Three of the 5 coated circuits (Trillium, Phisio and Bioline BCC) were found to improve ventilator and ICU time compared to Control. Further studies are indicated to validate these results and their impact upon approval criteria, purchasing choices and safe clinical practice, especially as applied to higher risk diabetic patients. [ABSTRACT FROM AUTHOR]

Because of their superior properties, titanium aluminium nitride (TiAlN) films are increasingly applied as protective layers on cutting and forming tools and turbine compressor blades and as biocompatible barriers. TiAlN films were deposited on AISI 316L stainless steel substrates by reactive magnetron sputtering using a target consisting of equal segments of titanium and aluminium. X-ray diffraction characterisation showed that the coating structure was face centred cubic. AFM and SEM studies indicated that the coatings are regular with dense shpherical granular structure. The coatings were also characterised using photoluminescence spectroscopy and Raman microscopy to elucidate the optical and acoustic phonon modes of the cubic lattices. Characteristic peaks were observed at 250, 620 and 1180 cm-1 in laser Raman studies. Polarisation and impedance spectroscopy studies on TiAlN and TiN coated specimens were conducted in Fusuyama simulated body fluid. The charge transfer resistance Rct increased in the order: uncoated 316L substrate; 2 μm TiN film; 3 μm TiN film; 2 μm TiAlN film. Thus, the TiAlN coating has the highest corrosion resistance, and was also found to have the most noble corrosion potential and lowest corrosion rate in the polarisation tests. [ABSTRACT FROM AUTHOR]

In this article, we present graphene oxide (produced by a modified Hummers' method) coatings obtained using two different methods: electrophoretic deposition on 316L stainless steel and chemical modification of the surface of gold applied to the steel. The coating properties were characterized by microscopic and spectrometric techniques. The contact angle was also determined, ranging from 50° to 70°. Our results indicated that GO coatings on steel and gold were not toxic towards L929 cells in a direct cell adhesion test—on all tested materials, it was possible to observe the growth of L929 cells during 48 h of culture. The lack of toxic effect on cells was also confirmed in two viability tests, XTT and MTT. For most of the tested materials, the cell viability was above 70%. They showed that the stability of the coating is the crucial factor for such GO coatings, and prove that GO in the form of coating is non-toxic; however, it can show toxicity if detached from the surface. The obtained materials also did not show any hemolytic properties, as the percentage of hemolysis was on the level of the negative control, which is very promising in the light of future potential applications. [ABSTRACT FROM AUTHOR]

Bioactive coatings on VT1-0 commercially pure titanium were formed by the plasma electrolytic oxidation (PEO). A study of the morphological features of coatings was carried out using scanning electron microscopy. A composition of formed coatings was investigated using energy-dispersive spectroscopy and X-ray diffractometry analysis. It was shown that PEO-coatings have calcium phosphate in their composition, which increases the bioactivity of the surface layer. Electrochemical properties of the samples were studied by potentiondynamic polarization and electrochemical impedance spectroscopy in different physiological media: simulated body fluid and minimum essential medium. The data of electrochemical studies indicate more than 15 times decrease in the corrosion current density for the sample with coating (5.0 × 10−9 A/cm2) as compared to the bare titanium (7.7 × 10−8 A/cm2). The formed PEO-layers have elastoplastic properties close to human bone (12–30 GPa) and a lower friction coefficient in comparison with bare metal. The wettability of PEO-layers increased. The contact angle for formed coatings reduced by more than 60° in comparison with bare metal (from 73° for titanium to 8° for PEO-coating). Such an increase in surface hydrophilicity contributes to the greater biocompatibility of the formed coating in comparison with commercially pure titanium. PEO can be prospective as a method for improving titanium surface bioactivity. [ABSTRACT FROM AUTHOR]

Plasma electrolytic oxidation (PEO) of Ti-15Mo alloys conducted in electrolytes containing Ca and P compounds can be an efficient process with which to obtain bioactive coatings. This paper reports on the influence of the nature of the electrolyte, its concentration, and PEO process parameters on the properties of anodized layers on Ti-15Mo. A wide range of Ca- and P-containing alkaline and acidic solutions was employed to incorporate Ca and P ions into the anodized layer. The efficiency of the incorporation was evaluated by the Ca/P ratio in the coating as compared to that in the electrolyte. It was found that alkaline solutions are not suitable electrolytes for the formation of good quality, uniform PEO coatings. Only acidic electrolytes are appropriate for obtaining well-adherent homogeneous layers on Ti-15Mo. However, the maximum Ca/P ratios reached in the coatings were rather low (close to 1). The variation of electrical signal (negative-to-positive current ratio, frequency) and time of electrolysis do not result in a substantial change of this value. The processing time, however, did influence the coating thickness. Despite their low Ca/P ratio, the anodized layers demonstrate good biological activity, comparable to pure microrough titanium. [ABSTRACT FROM AUTHOR]