标题：Nickel, molybdenum, and tungsten nanoparticle-dispersed alkylalkoxysilane polymer for biomaterial coating: evaluation of effects on bacterial biofilm formation and biosafety
摘要：Biofilm formation on the surfaces of biomaterials can cause severe infectious diseases due to of inefficiency of antibiotics against biofilm-protected pathogens. On one hand, the prevention of biofilm formation is a critical issue in the development of biomaterials. On the other hand, biomaterials require biological compatibility. To achieve these two goals without compromising the original features of the biomaterial, we proposed metal nanoparticle (NP)-dispersed alkylalkoxysilane (AAS) coatings. Here, we chose nickel, molybdenum, and tungsten, components of stainless steel and other alloys for biomaterials, as prospective metals that could regulate biofilm formation without harming human health. To the best of our knowledge, this is the first report to describe the effect of tungsten on biofilm formation. We performed a biofilm formation test using an open laboratory biofilm reactor that utilizes tap water and environmental bacteria from the laboratory air, and we also performed a cytotoxicity test on the human monocyte-derived U937 cell line. Compared with the AAS polymer alone, nickel NP-dispersed AAS polymer exhibited an inhibitory activity against biofilm formation whereas tungsten and molybdenum NP-dispersed AAS polymers facilitated biofilm formation. The effect of tungsten was dose-dependent. At a low metal concentration (0.1 mol%), the NP-dispersed AAS polymers did not affect cell survival. These results showed that for nickel, molybdenum, and tungsten, the NP-dispersed AAS polymers exhibited biosafety and that the nickel NP-dispersed AAS polymer is suitable for inhibiting biofilm formation. To determine whether molybdenum (or tungsten) NP-dispersed AAS polymer is suitable for biomaterial application, further evaluation in an environment that mimics the human body with clinically relevant pathogens is necessary.
