Microbial colonization and biofilm formation on implanted devices represent an important complication in orthopaedic and dental surgery and may result in implant failure. Controlled release of antibacterial agents directly at the implant site may represent an effective approach to treat these chronic complications. Resistance to conventional antibiotics by pathogenic bacteria has emerged in recent years as a major problem of public health. In order to overcome this problem, non-conventional antimicrobial agents have been under investigation. In this study, polyacrylate-based hydrogel thin coatings have been electrosynthesised on titanium substrates starting from poly(ethylene glycol diacrylate)-co-acrylic acid. Silver nanoparticles (AgNPs) with a narrow size distribution have been synthesized using a "green" procedure and immobilized on Ti implant surfaces exploiting hydrogel coatings' swelling capabilities. The coatings have been characterized by XPS and SEM/EDX, while their silver release performances have been monitored by ICP-MS. The antibacterial activity of these AgNP-modified hydrogel coatings was tested evaluating in vitro inhibition growth of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli, among the most common pathogens in orthopaedic infections. Moreover, a preliminary investigation of the biocompatibility of silver-loaded coatings versus MG63 human osteoblast-like cells has been performed. An important point of strength of this paper, in fact, is the concern about the effect of silver species on the surrounding cell system in implanted medical devices. Silver ion release has been properly tuned in order to assure antibacterial activity while preserving osteoblasts' response at the implant interface.

Research on the nanomaterials containing\ud one or more transition metals is growing tremendously,\ud thanks to the large number of preparation processes available\ud and to the novel applications that can be envisaged\ud in several fields. This review presents an overview of\ud the selected studies in the field of antimicrobial textiles,\ud employing bioactive nanophases of elements/compounds\ud such as silver, copper, or zinc oxide. In addition, the history\ud of use of these antimicrobials and their mechanism\ud of action are shortly reported. Finally, a short description\ud is provided of the deposition/preparation methods, which\ud are being used in the authors ’ labs for the development\ud of the textiles modified by the novel nanoantimicrobial

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In this study, a preventive method for fighting bio-deterioration of stone substrates is proposed. This is\ud based on the use of bioactive zinc oxide nanoparticles (ZnO-NPs), which are able to exert a marked\ud biological activity over a long period of time due to their peculiar structure. ZnO-NPs are synthesised by\ud a simple and reproducible electrochemical procedure. The nanomaterials are embedded in consolidant/\ud water-repellent matrices to obtain nanostructured coatings. Commonly used products based on\ud tetraethoxysilane and/or polysiloxanes were tested. The resulting nanomaterials were fully characterised\ud by X-ray photoelectron spectroscopy (XPS) to investigate the amount and composition of the NPs and\ud the behaviour of the nanocomposites. Inductively coupled plasma mass spectrometry (ICP-MS) was\ud used for the study of the release of metal from the composites when put in contact with artificial\ud rainwater. The nanocomposites were applied to specimens composed of three different types of stone\ud and chromatic changes upon curing were measured by spectrophotocolorimetry. Finally, morphological\ud characterization by scanning electron microscopy (SEM) was performed. The bioactivity of ZnO-NPs\ud nanocomposites was also assessed in preliminary tests against Aspergillus niger fungu