Green Synthesis of Protein Stabilized Silver Nanoparticles Using Pseudomonas fluorescens, a Marine Bacterium, and Its Biomedical Applications When Coated on Polycaprolactam

Green synthesis of protein stabilized silver nanoparticles (AgNPs) using the supernatant of a marine isolate, Pseudomonas fluorescens PMMD3 (P.fluorescens), and its biomedical applications and biocompatibility when coated on polycaprolactam is reported here. The AgNPs are spherical and are 1–10 nm in size. AgNP-coated polycaprolactam showed 89.7% and 92.4% reduction in colony forming units (CFUs), when compared to bare polymer, against S.aureus and E.coli, respectively. In the biofilm on AgNP composite, when compared to the bare polymer, there were carbohydrate reductions by factors of 3.5 and 6.0 in S.aureus and E.coli biofilm, respectively, and protein reductions by factors of 6.5 and 3.0 in S.aureus and E.coli biofilm, respectively. Reduction in the adhesion of S.aureus, C.albicans, A.niger, and F.proliferatum were observed using scanning electron microscopy (SEM) and fluorescence microscopy. The C.albicans biofilm is 15 and 6 μm thick on polycaprolactam and AgNP composite, respectively. We observed 84% and 80% proliferation of 3T3-L1 adipocyte cells and 85% and 97% of L929 fibroblast on the AgNP composite and bare polymer, indicating that this new material is suitable for biomaterial applications.