Despite technological advancement,
nosocomial infections are prevalent due to the rise of antibiotic resistance. A combinatorial approach with multimechanistic antibacterial activity is desired for an effective antibacterial medical device surface strategy. In this study, an
antimicrobial peptide,
nisin, is immobilized onto biomimetic
nitric oxide (NO)-releasing medical-grade
silicone rubber (SR) via mussel-inspired
polydopamine (PDA) as a bonding agent to reduce the risk of
infection. Immobilization of
nisin on NO-releasing SR (SR-SNAP-
Nisin) and the surface characteristics were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectroscopy and contact angle measurements. The NO release profile (7 days) and diffusion of SNAP from SR-SNAP-
Nisin were quantified using chemiluminescence-based
nitric oxide analyzers and UV-vis spectroscopy, respectively.
Nisin quantification showed a greater affinity of
nisin immobilization toward SNAP-doped SR. Matrix-assisted
laser desorption/ionization mass spectrometry analysis on surface
nisin leaching for 120 h under physiological conditions demonstrated the stability of
nisin immobilization on PDA coatings. SR-SNAP-
Nisin shows versatile in vitro anti-
infection efficacy against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus in the planktonic and adhered states. Furthermore, the combination of NO and
nisin has a superior ability to impair biofilm formation on
polymer surfaces. SR-SNAP-
Nisin leachates did not elicit cytotoxicity toward mouse fibroblast cells and human umbilical vein endothelial cells, indicating the biocompatibility of the material in vitro. The preventative and therapeutic potential of SR-SNAP-
Nisin dictated by two bioactive agents may offer a promising antibacterial surface strategy.