Bacterial colonization on medical device surfaces can lead to infection, loss of device functionality, and in the worst case, death. Due to the recent rise in antimicrobial resistance, alternative surface design strategies are applied to prevent medical device-related infection. In this study, an antimicrobial peptide, nisin, was immobilized onto nitric oxide (NO)-releasing polydimethylsiloxane (PDMS) via the assistance of polydopamine (PDA) as a primer layer (hereafter PDMS-SNAP-Nisin). The surface was characterized through fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX), and contact angle measurements to confirm nisin immobilization. PDMS-SNAP-Nisin produced sustained, physiologically relevant NO surface flux for 7 d. The synergistic combination of nisin and NO demonstrated enhanced in vitro antibacterial efficacy against Gram-positive S. aureus and Gram-negative E. coli in planktonic and adhered states. SEM analysis of E. coli on the modified PDMS surface revealed morphological deformation and rupture of the cell envelope. Biofilm formation on PDMS-SNAP-Nisin surfaces was significantly reduced compared to control PDMS. Additionally, the material surface did not elicit cytotoxicity towards mouse fibroblast cells and human umbilical vein endothelial cells (HUVEC). Therefore, the superior antibacterial efficacy with minimal cytotoxicity of PDMS-SNAP-Nisin has promising biomedical potential.

Antibacterial efficacy of polydopamine-assisted nisin immobilized nitric oxide-releasing polydimethylsiloxane

ACS Fall 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.