by Keyword: Implants

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Rodríguez-Contreras, A., Torres, D., Guillem-Marti, J., Sereno, P., Ginebra, M. P., Calero, J. A., Manero, J. M., Rupérez, E., (2020). Development of novel dual-action coatings with osteoinductive and antibacterial properties for 3D-printed titanium implants Surface and Coatings Technology 403, 126381

Gallium (Ga) has been recently proposed as a novel therapeutic agent, since it promotes bone formation and exhibits antibacterial properties. This work focuses on the optimization of a thermochemical treatment that incorporates Ga ions by the addition of the body-friendly Ga nitrate approved by the Food and Drug Administration. The objective was to simultaneously provide the inner and the outer surfaces of porous‑titanium surfaces obtained by 3D-printing with bioactivity and antibacterial properties. The apatite-forming ability of the coating, as well as the antibacterial activity and SaOS-2 cell adhesion, proliferation, differentiation and mineralization were evaluated and compared with untreated Ti surfaces. The characterization of the surfaces revealed the presence of a Ga-containing calcium titanate layer, which was non cytotoxic and in simulated body fluid produced a homogeneous apatite coating well adhered to the substrate. The formation of this apatite layer was accelerated with increasing Ga amounts present on the surface, resulting also in an increase in thickness. An initial quick release of Ga ion promoted the antibacterial effect against gram positive strains, especially for Pseudomonas aeruginosa, one of the most frequent resistant pathogens in nosocomial infections. SaOS-2 cells adhered and proliferated on the Ga-doped Ti surfaces, its presence contributed to cell differentiation and to considerably increase the mineralization levels. Thus, the developed multifunctional coatings could provide bioactivity to the porous Ti implants while protecting them from the most frequent gram-negative pathogens.

Keywords: 3D-printing, Antibacterial activity, Biomaterials, Gallium, Porous structures, Titanium implants

Lanzalaco, S., Turon, P., Weis, C., Mata, C., Planas, E., Alemán, C., Armelin, E., (2020). Toward the new generation of surgical meshes with 4D response: Soft, dynamic, and adaptable Advanced Functional Materials 30, (36), 2004145

Herein, a facile approach toward transforming a 2D polypropylene flexible mesh material into a 4D dynamic system is presented. The versatile platform, composed by a substrate of knitted fibers of isotactic polypropylene (iPP) mesh and a coating of thermosensitive poly(N‐isopropylacrylamide‐co‐N,N’‐methylene bis(acrylamide) (PNIPAAm‐co‐MBA) hydrogel, covalently bonded to the mesh surface, after cold‐plasma surface treatment and radical polymerization, is intended to undergo variations in its geometry via its reversible folding/unfolding behavior. The study is the first to trace the 3D movement of a flat surgical mesh, intended to repair hernia defects, under temperature and humidity control. An infrared thermographic camera and an optical microscope are used to evaluate the macroscopic and microscopic structure stimulus response. The presence of the PP substrate and the distribution of the gel surrounding the PP threads, affect both the PNIPAAM gel expansion/contraction as well as the time of folding/unfolding response. Furthermore, PP‐g‐PNIPAAm meshes show an increase in the bursting strength of ≈16% with respect to the uncoated mesh, offering a strongest and adaptable system for its future implantation in human body. The findings reported offer unprecedented application possibilities in the biomedical field.

Keywords: Dynamic devices, Polypropylene meshes, Surgical implants, Thermosensitive hydrogels

Mir, M., Lugo, R., Tahirbegi, I. B., Samitier, J., (2014). Miniaturizable ion-selective arrays based on highly stable polymer membranes for biomedical applications Sensors 14, (7), 11844-11854

Poly(vinylchloride) (PVC) is the most common polymer matrix used in the fabrication of ion-selective electrodes (ISEs). However, the surfaces of PVC-based sensors have been reported to show membrane instability. In an attempt to overcome this limitation, here we developed two alternative methods for the preparation of highly stable and robust ion-selective sensors. These platforms are based on the selective electropolymerization of poly(3,4-ethylenedioxythiophene) (PEDOT), where the sulfur atoms contained in the polymer covalently interact with the gold electrode, also permitting controlled selective attachment on a miniaturized electrode in an array format. This platform sensor was improved with the crosslinking of the membrane compounds with poly(ethyleneglycol) diglycidyl ether (PEG), thus also increasing the biocompatibility of the sensor. The resulting ISE membranes showed faster signal stabilization of the sensor response compared with that of the PVC matrix and also better reproducibility and stability, thus making these platforms highly suitable candidates for the manufacture of robust implantable sensors.

Keywords: Biomedicine, Electrochemistry, Endoscope, Implantable device, Ion-selective electrode (ISE) sensor, Ischemia, pH detection, Biocompatibility, Chemical sensors, Electrochemistry, Electrodes, Electropolymerization, Endoscopy, Functional polymers, Implants (surgical), Ion selective electrodes, Medical applications, Polyvinyl chlorides, Stabilization, Biomedical applications, Biomedicine, Implantable devices, Ion selective sensors, Ischemia, Membrane instability, pH detection, Poly(3 ,4 ethylenedioxythiophene) (PEDOT), Ion selective membranes

Tahirbegi, I. B., Alvira, M., Mir, M., Samitier, J., (2014). Simple and fast method for fabrication of endoscopic implantable sensor arrays Sensors 14, (7), 11416-11426

Here we have developed a simple method for the fabrication of disposable implantable all-solid-state ion-selective electrodes (ISE) in an array format without using complex fabrication equipment or clean room facilities. The electrodes were designed in a needle shape instead of planar electrodes for a full contact with the tissue. The needle-shape platform comprises 12 metallic pins which were functionalized with conductive inks and ISE membranes. The modified microelectrodes were characterized with cyclic voltammetry, scanning electron microscope (SEM), and optical interferometry. The surface area and roughness factor of each microelectrode were determined and reproducible values were obtained for all the microelectrodes on the array. In this work, the microelectrodes were modified with membranes for the detection of pH and nitrate ions to prove the reliability of the fabricated sensor array platform adapted to an endoscope.

Keywords: Chemical sensors, Cyclic voltammetry, Electrochemistry, Endoscopy, Fabrication, Implants (surgical), Microelectrodes, Needles, Nitrates, Scanning electron microscopy, Biomedicine, Fabricated sensors, Fabrication equipment, Implantable devices, Implantable sensors, Optical interferometry, Planar electrode, Roughness factor, Ion selective electrodes

Juanola-Feliu, E., Colomer-Farrarons, J., Miribel-Català , P., Samitier, J., Valls-Pasola, J., (2012). Market challenges facing academic research in commercializing nano-enabled implantable devices for in-vivo biomedical analysis Technovation , 32, (3-4), 193-204

This article reports on the research and development of a cutting-edge biomedical device for continuous in-vivo glucose monitoring. This entirely public-funded process of technological innovation has been conducted at the University of Barcelona within a context of converging technologies involving the fields of medicine, physics, chemistry, biology, telecommunications, electronics and energy. The authors examine the value chain and the market challenges faced by in-vivo implantable biomedical devices based on nanotechnologies. In so doing, they trace the process from the point of applied research to the final integration and commercialization of the product, when the social rate of return from academic research can be estimated. Using a case-study approach, the paper also examines the high-tech activities involved in the development of this nano-enabled device and describes the technology and innovation management process within the value chain conducted in a University-Hospital-Industry-Administration-Citizens framework. Here, nanotechnology is seen to represent a new industrial revolution, boosting the biomedical devices market. Nanosensors may well provide the tools required for investigating biological processes at the cellular level in vivo when embedded into medical devices of small dimensions, using biocompatible materials, and requiring reliable and targeted biosensors, high speed data transfer, safely stored data, and even energy autonomy.

Keywords: Biomedical device, Diabetes, Innovation management, Nanobiosensor, Nanotechnology, Research commercialization, Technology transfer, Academic research, Applied research, Barcelona, Biocompatible materials, Biological process, Biomedical analysis, Biomedical devices, Cellular levels, Converging technologies, Glucose monitoring, High-speed data transfer, Implantable biomedical devices, Implantable devices, In-vivo, Industrial revolutions, Innovation management, Medical Devices, Nanobiosensor, Rate of return, Research and development, Technological innovation, Value chains, Biological materials, Biomedical engineering, Biosensors, Commerce, Data transfer, Earnings, Engineering education, Glucose, Implants (surgical), Industrial research, Innovation, Medical problems, Nanosensors, Nanotechnology, Technology transfer, Equipment

Hristova, K., Pecheva, E., Pramatarova, L., Altankov, G., (2011). Improved interaction of osteoblast-like cells with apatite-nanodiamond coatings depends on fibronectin Journal of Materials Science: Materials in Medicine , 22, (8), 1891-1900

New apatite (AP)/nanodiamond (ND) coating has been developed to improve physical and biological properties of stainless steel (SS) versus single AP coating. Homogeneously electrodeposited AP-ND layer demonstrates increased mechanical strength, interlayer cohesion and ductility. In the absence of serum, osteoblast-like MG63 cells attach well but poorly spread on both AP and AP-ND substrata. Pre-adsorption with serum or fibronectin (FN) improves the cellular interaction-an effect that is better pronounced on the AP-ND coating. In single protein adsorption study fluorescein isothiocyanate-labeled FN (FITC-FN) shows enhanced deposition on the AP-ND layer consistent with the significantly improved cell adhesion, spreading and focal adhesions formation (in comparison to SS and AP), particularly at low FN adsorption concentrations (1 mu g/ml). Higher FN concentrations (20 mu g/ml) abolish this difference suggesting that the promoted cellular interaction of serum (where FN is low) is caused by the greater affinity for FN. Moreover, it is found that MG63 cells tend to rearrange both adsorbed and secreted FN on the AP-ND layer suggesting facilitated FN matrix formation.

Keywords: Extracellular-matrix, Protein adsorption, Integrins, Adhesion, Biomaterials, Surfaces, Polymerization, Composite, Implants, Titanium