Biofilm inhibiting nanocomposite coatings—a promising alternative to combat surgical site infections

Surface texture modification for reducing physical adherence of bacteria can be a critical alternative to conventional antimicrobials, especially in the case of surgical accessories. In the present study, a nanocomposite hydrophobic coating formulation exhibiting biofilm-inhibiting properties was developed. The formulation alone and in combination with a biocide (chitosan) was deposited by dip-coating on different substrates like cover glass slips, acrylonitrile butadiene styrene (ABS) coupons, and surgical sutures made of polyglactin, nylon, and silk. The coated substrates were characterized for their roughness, wetting behavior, and surface morphology. Biofilm inhibition by the formulation when coated on various substrates was evaluated against multiple bacterial strains, namely Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecium, Escherichia coli, and Acinetobacter baumannii sourced both from ATCC and clinical cases. The nanocomposite coatings were found to exhibit substantial biofilm inhibition against all tested bacterial strains. The biofilm inhibition property of the nanocomposite-coated polyglactin suture was found to be higher (59–67%) when compared with commercially available antibacterial sutures, whose percentage biofilm inhibition was found to be 43–48% when tested against clinical isolates of S. aureus, P. aeruginosa, and A. baumannii.