Staphylococcus epidermidis has emerged as one of the major nosocomial pathogens associated with infections of implanted medical devices. The initial adhesion of these organisms to the surface of biomaterials is assumed to be an important stage in their colonization. The main objective of this work is to assess the influence of surface features on the adhesion of S. epidermidis to Ag–TiCN coatings deposited by dc reactive magnetron sputtering. The structural results obtained by x-ray diffraction show that the coatings crystallize in a B1-NaCl crystal structure typical of TiC0.3N0.7. The increase of Ag content promoted the formation of Ag crystalline phases. According to the results obtained with atomic force microscopy, a decrease on the surface roughness of the films from 39 to 7 nm is observed as the Ag content increases from 0 to 15 at.%. Surface energy results show that the increase of Ag promotes an increase in hydrophobicity. Bacterial adhesion and biofilm formation on coatings were assessed by the enumeration of the number of viable cells. The results showed that the surface with lower roughness and higher hydrophobicity leads to greater bacterial adhesion and biofilm formation, highlighting that surface morphology and hydrophobicity rule the colonization of materials.

With the increase of elderly population and the health problems arising nowadays, such as cancer, knee and hip joint prostheses are widely used worldwide. It is estimated that 20% of hip replacement surgeries simply fail after 5years, due to wear loosening, instability and infection. In this paper it is reported the study of advanced materials with the ability to overcome some of these drawbacks. The development of ceramic coatings, based on carbonitrides of transition metals, such as TiCN, doped with silver, Ag, may represent an effective solution. Thin films of Ag-TiCN were produced by dc reactive magnetron sputtering with silver contents ranging from 4 to 8at.%. The physical, chemical, structural, morphological/topographical, mechanical and tribological properties were evaluated. The tribological tests were performed in a unidirectional wear simulator, pin on disk, being the antagonists of a ceramic Al2O3 ball, and using simulate body fluids as lubricant. Hank's Balanced Salt Solution (HBSS) and bovine serum albumin (BSA) in HBSS were chosen, in order to evaluate the lubrication ability of the solution containing the protein, albumin. The results revealed that the coatings with Ag content ranging from 4 to 8at.%, were the most promising, as the tribological properties were superior to the results reported by other authors, which also developed Ag-TiCN coatings containing similar Ag contents and using similar test conditions. The presence of albumin leads to a lower wear in all the test conditions, and this enhancement was higher in the hydrophobic surfaces.

Nanoporous tantalum oxide (Ta2O5) attraction has been increasing due its high variety of applications, from protective coatings, photocatalysts to biomedical devices. Anodization is a surface modification technique, inexpensive, versatile and easily scalable, widely used to produce these nanostructures. In this work, Ta2O5 nanoporous surface were produced by anodization in a non-aqueous HF-free electrolyte composed by ethylene glycol, water and ammonium fluoride (NH4F), for different anodization parameters (electrolyte concentration, applied potential and time) and comparing a two-step with one-step anodization process. The surface morphology of each sample was investigated by scanning electron microscopy (SEM) and the sample with the optimized nanostructure was characterized in terms of cross-section morphology, chemical composition and crystalline structure. The concentration of NH4F and applied potential demonstrated a

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ZrCN coatings with incorporated silver were deposited on 316L stainless steel by dual reactive magnetron sputtering to evaluate the silver influence on the structural properties and corrosion resistance of the films. Samples composition was assessed by electron probe microanalysis.Glow discharge optical emission spectroscopy was used to determine the distribution of silver in the films. Structural characterization was performed by X-ray diffraction and Raman spectroscopy. Corrosion resistance was evaluated by potentiodynamic test and electrochemical impedance spectroscopy. Results revealed enhanced corrosion resistance properties of the coated steel and higher coatings reactivity when incorporated with silver, showing a plausible silver release increment.