A biocompatible new titanium alloy Ti–16Hf–25Nb with low elastic modulus (45 GPa) and the use of short bioadhesive peptides derived from the extracellular matrix have been studied. In terms of cell adhesion, a comparative study with mixtures of short peptides as RGD (Arg‐Gly‐Asp)/PHSRN (Pro‐His‐Ser‐Arg‐Asn) and RGD (Arg‐Gly‐Asp)/FHRRIKA (Phe‐His‐Arg‐Arg‐Ile‐Lys‐Ala) have been carried out with rat mesenchymal cells. The effect of these mixtures of short peptides have already been studied but there are no comparative studies between them. Despite the wide variety of silane precursors available for surface modification in pure titanium, the majority of studies have used aminosilanes, in particular 3‐minopropyltriethoxysilane (APTES). Nevertheless, the 3‐chloropropyltriethoxysilane (CPTES) is, recently, proposed by other authors. Unlike APTES, CPTES does not require an activation step and offers the potential to directly bind the nucleophilic groups present on the biomolecule (e.g., amines or thiols). Since the chemical surface composition of this new alloy could be different to that pure titanium, both organosilanes have been compared and characterized by means of a complete surface characterization using contact angle goniometry and X‐ray photoelectron spectroscopy. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B:495–502, 2015.

Magnesium alloys have been extensively studied as degradable biomaterials for clinical applications due to their biocompatibility and mechanical properties. However, their poor corrosion resistance can lead to issues such as osteolysis and the release of gaseous hydrogen. This study investigated the influence of the activation time of magnesium surfaces in a sodium hydroxide (NaOH) solution on the concentration of active hydroxyl groups and corrosion resistance. The results indicated that immersion time significantly influences the formation of a corrosion-resistant film and the distribution of surface hydroxyl groups. Specifically, specimens treated for 7.5 h exhibited the highest concentration of hydroxyl groups and the most uniform oxide film distribution. Electrochemical tests demonstrated capacitive behavior and passive surface formation for all evaluated times, with the 7.5-h immersion in NaOH yielding superior corrosion resistance, lower current density, and a more efficient and thicker protective film. SEM and EDS analyses confirmed increased formation of Mg(OH)₂ for samples treated for 5 and 7.5 h, while a 10-h treatment resulted in a brittle, porous layer prone to degradation. Statistical analysis using ANOVA and Fisher's LSD test corroborated these findings. The optimal 7.5-h alkali treatment enhanced magnesium's corrosion resistance and surface properties, making it a promising candidate for orthopedic implants. However, further studies are necessary to assess biocompatibility and physiological responses before clinical implementation.

Atmospheric contaminants from marine-industrial environments could cause corrosion damage on steel A36 usually used in equipment and machinery. Therefore, it is desirable to study the corrosion phenomena in different microenvironments and formulate adequate protection measures. In this study, three microenvironments were selected and categorized according to ISO-12944-2 standard as C5-I and C5-M. Four multilayer-coating schemes were used on each exposure site to evaluate their performance. Corrosion products were analyzed using x-ray diffraction, Raman, and ultraviolet-visible techniques. The results showed that the best system was composed of a flake-filled-epoxy/polyamides/epoxy-siloxane. The results confirmed the influence of atmospheric contaminants on overall behavior from different locations.