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Background Bacterial biofilm can occur on all medical implanted devices and lead to infection and/or dysfunction of the device. In this study, artificial biofilm was formed on four different medical implants (silicone, piccline, peripheral venous catheter and endotracheal tube) of interest for our daily clinical and/or research practice. We investigated the best conventional technic to dislodge the biofilm on the implants and quantified the number of bacteria. Staphylococcus epidermidis previously isolated from a breast implant capsular contracture on a patient in the university hospital of Dijon was selected for its ability to produce biofilm on the implants. Different technics (sonication, Digest-EUR®, mechanized bead mill, combination of sonication plus Digest-EUR®) were tested and compared to detach the biofilm before quantifying viable bacteria by colony counting. Results For all treatments, the optical and scanning electron microscope images showed substantial less biofilm biomass remaining on the silicone implant compared to non-treated implant. This study demonstrated that the US procedure was statistically superior to the other physical treatment: beads, Digest-EUR® alone and Digest-EUR® + US ( p  < 0.001) for the flexible materials (picc-line, PIV, and silicone). The number of bacteria released by the US is significantly higher with a difference of 1 log on each material. The result for a rigid endotracheal tube were different with superiority for the chemical treatment dithiothreitol: Digest-EUR®. Surprisingly the combination of the US plus Digest-EUR® treatment was consistently inferior for the four materials. Conclusions Depending on the materials used, the biofilm dislodging technique must be adapted. The US procedure was the best technic to dislodge S. epidermidis biofilm on silicone, piccline, peripheral venous catheter but not endotracheal tube. This suggested that scientists should compare themselves different methods before designing a protocol of biofilm study on a given material.

Background: The delivery of therapeutic genes in sites of articular cartilage lesions using non-invasive, scaffold-guided gene therapy procedures is a promising approach to stimulate cartilage repair while protecting the cargos from detrimental immune responses, particularly when targeting chondroreparative bone marrow-derived mesenchymal stromal cells in a natural microenvironment like marrow aspirates. Methods: Here, we evaluated the benefits of providing a sequence for the cartilage-specific sex-determining region Y-type high-mobility group box 9 (SOX9) transcription factor to human marrow aspirates via recombinant adeno-associated virus (rAAV) vectors delivered by poly(ε-caprolactone) (PCL) films functionalized via grafting with poly(sodium styrene sulfonate) (pNaSS) to enhance the marrow chondrogenic potential over time. Results: Effective sox9 overexpression was observed in aspirates treated with pNaSS-grafted or ungrafted PCL films coated with the candidate rAAV-FLAG-hsox9 (FLAG-tagged rAAV vector carrying a human sox9 gene sequence) vector for at least 21 days relative to other conditions (pNaSS-grafted and ungrafted PCL films without vector coating). Overexpression of sox9 via rAAV sox9/pNaSS-grafted or ungrafted PCL films led to increased biological and chondrogenic differentiation activities (matrix deposition) in the aspirates while containing premature osteogenesis and hypertrophy without impacting cell proliferation, with more potent effects noted when using pNaSS-grafted films. Conclusions: These findings show the benefits of targeting patients’ bone marrow via PCL film-guided therapeutic rAAV (sox9) delivery as an off-the-shelf system for future strategies to enhance cartilage repair in translational applications.

The world of biomaterials has been continuously evolving. Where in the past only mono-material implants were used, the growth in technology and collaboration between researchers from different sectors has led to a tremendous improvement in implant industry. Nowadays, composite materials are one of the leading research areas for biomedical applications. When we look toward hard tissue applications, metal-based composites seem to be desirable candidates. Metals provide the mechanical and physical properties needed for load-bearing applications, which when merged with beneficial properties of bioceramics/polymers can help in the creation of remarkable bioactive as well biodegradable implants. Keeping this in mind, this review will focus on various production routes of metal-based composite materials for hard tissue applications. Where possible, the pros and cons of the techniques have been provided.

A challenge in contractile restoration of myocardial scars is one of the principal aims in cardiovascular surgery. Recently, a new potent biological tool used within healing processes is represented by exosomes derived from mesenchymal stem cells (MSCs). These cells are the well-known extracellular nanovesicles released from cells to facilitate cell function and communication. In this work, a combination of elastomeric membranes and exosomes was obtained and tested as a bioimplant. Mesenchymal stem cells (MSCs) and macrophages were seeded into the scaffold (polycaprolactone) and filled with exosomes derived from MSCs. Cells were tested for proliferation with an MTT test, and for wound healing properties and macrophage polarization by gene expression. Moreover, morphological analyses of their ability to colonize the scaffolds surfaces have been further evaluated. Results confirm that exosomes were easily entrapped onto the surface of the elastomeric scaffolds, increasing the wound healing properties and collagen type I and vitronectin of the MSC, and improving the M2 phenotype of the macrophages, mainly thanks to the increase in miRNA124 and decrease in miRNA 125. We can conclude that the enrichment of elastomeric scaffolds functionalized with exosomes is as an effective strategy to improve myocardial regeneration.

Currently, bone tissue repair has emerged as a critical medical priority worldwide, largely due to the rising human life expectancy. Although bone grafting remains the standard treatment, it faces sustainability challenges and is often associated with complications such as infections, which can require further surgery or, in severe cases, lead to amputation. To address these issues, researchers are increasingly focusing on biodegradable scaffolds that support tissue regeneration by promoting cellular differentiation. This study aims to enhance the cellular response of a porous scaffold designed through 3D printing. Using a wire deposition modeling approach, we developed cylindrical scaffolds with triangular pores. Then, a vinylbenzylphosphonic acid monomer was polymerized and covalently anchored as poly(vinyl benzyl phosphonic acid) onto the scaffold surface through a two-step UV irradiation grafting process. Characterization techniques, including colorimetric assays and infrared spectroscopy, confirmed the successful poly(vinyl benzyl phosphonic acid) deposition onto the sample surface. Furthermore, scanning electron microscopy, size exclusion chromatography and differential scanning calorimetry further validated that the fabrication and grafting processes, maintening the structural integrity and intrinsic properties of the implants. Finally, cell viability assays revealed improved survival rates of MC3T3-E1 pre-osteoblasts, while mineralization assays indicated enhanced and accelerated cellular differentiation with the effect of porous scaffold and post-grafting.

Poly(dimethyl siloxane) (PDMS) is one of the most widely used materials in the biomedical field. Despite its numerous advantages, its hydrophobic character promotes bacterial adhesion and biofilm formation. For breast implants, biocompatibility is challenged due to the biofilm formed around the implant that can degenerate to severe capsular contracture over time. Thus, the laboratory has set up strategies to prevent bacterial contamination by grafting covalently hydrophilic bioactive polymers on the surface of implants. In this study, poly(methacrylic acid) (PMAc) and poly(acrylic acid) (PAAc) were chosen as non-toxic and biocompatible bioactive polymers known for reducing bacteria adhesion. These polymers are also good candidates to lend reactivity on the surface for further functionalization. X-ray photoelectron Spectroscopy (XPS) and Fourier-Transform Infrared spectroscopy (FTIR) analysis have highlighted the covalent grafting of these polymers. Apparent water contact angle measurements have shown the change in hydrophilicity on the surface, and a colorimetric assay allowed us to assess the grafting rate of PMAc and PAAc. Tensile strength assays were performed to ensure that the functionalization process does not significantly alter the material’s mechanical properties. Analyses of the surface aspect and roughness by Scanning Electron Microscope (SEM) and optical profilometer allow us to formulate hypotheses to approach the understanding of the behavior of the polymer once grafted.

In this study, the characteristics of nanocrystalline diamond films synthesized at low surface temperature on Ti-6Al-4V (TA6V) substrates using a distributed antenna array microwave reactor aiming at biomedical applications were investigated. The surface roughness of the TA6V substrates is varied by scratching with emery paper of 1200, 2400, 4000 polishing grit. Nanocrystalline diamond (NCD) coatings with morphology, purity, and microstructure comparable to those obtained on silicon substrates usually employed in the same reactor and growth conditions are successfully achieved whatever the polishing protocol. However, the latter has a significant effect on the roughness parameters and hardness of the NCD films. The use of the finest polishing grit thus permits us to enhance the hardness value, which can be related to the work-hardening phenomenon arising from the polishing process.

Currently, bone tissue repair has emerged as a critical medical priority worldwide, largely due to the rising human life expectancy. Although bone grafting remains the standard treatment, it faces sustainability challenges and is often associated with complications such as infections, which can require further surgery or, in severe cases, lead to amputation. To address these issues, researchers are increasingly focusing on biodegradable scaffolds that support tissue regeneration by promoting cellular differentiation. This study aims to enhance the cellular response of a porous scaffold designed through 3D printing. Using a wire deposition modeling approach, we developed cylindrical scaffolds with triangular pores. Then, a vinylbenzylphosphonic acid monomer was polymerized and covalently anchored as poly(vinyl benzyl phosphonic acid) onto the scaffold surface through a two-step UV irradiation grafting process. Characterization techniques, including colorimetric assays and infrared spectroscopy, confirmed the successful poly(vinyl benzyl phosphonic acid) deposition onto the sample surface. Furthermore, scanning electron microscopy, size exclusion chromatography and differential scanning calorimetry further validated that the fabrication and grafting processes, maintening the structural integrity and intrinsic properties of the implants. Finally, cell viability assays revealed improved survival rates of MC3T3-E1 pre-osteoblasts, while mineralization assays indicated enhanced and accelerated cellular differentiation with the effect of porous scaffold and post-grafting.

Bacterial adhesion, biocompatibility and biointegration on implanted prosthetic materials represent major problems for public health. The use of bioactive polymers has been shown to be an excellent solution. Several techniques for covalently tethering well‐defined polymer brushes onto surfaces have been developed, including the covalent attachment of end‐functionalized polymers incorporating an appropriate anchor (“grafting to”) or the in situ polymerization initiated from the surface (“grafting from”). The grafting to method for functionalizing stainless steel (SS) surfaces is based on the use of a readily accessible anchor incorporating both an anchoring group that is capable of forming, under mild condition, a robust stable layer and a reactive function facilitating the modular and efficient post functionalization of SS surfaces. Anterior cruciate ligament (ACL) rupture is the most common sport injury and due to its poor healing capacity, surgical treatments are often required for restoring the function of the knee.

The development of advanced materials for biomedical implants has made significant progress in the search for biomaterials with functional surfaces which enhance compatibility, prevent implant corrosion, and reduce the growth of microorganisms in the form of biofilms. This article reviews various materials used in implants, among which yttria-stabilized zirconia (YSZ) and hydroxyapatite (HAp) stand out due to their unique properties which favor osseointegration. Additionally, strategies for doping with additional elements, notably the addition of silver for its antimicrobial properties, are highlighted. Different methods of coating implant surfaces with these materials are evaluated. Finally, it is concluded that multilayer coating systems [YSZ/HAp-Ag]n significantly improve corrosion resistance, biocompatibility, and the ability to inhibit bacterial proliferation in implants. Implementing these implant coatings could increase their durability and effectiveness in biomedical applications, contributing to better integration into bone tissue and reducing postoperative infections.