Effect of antimicrobial peptide (AMP)–tethered stainless steel surfaces on the bacterial membrane

Bacterial colonization leading to biofilm formation on surfaces induces industry-related as well as health care–associated infections worldwide. Emerging antibiotic-resistant microbes and related persistent infections due to adherent biofilm formation on surfaces have urged the need of effective alternative solutions to eradicate prevailing problems. Antimicrobial peptides are considered as potential candidates with distinguished characteristics, namely, broad-spectrum antimicrobial activity, low propensity toward pathogen resistance, and low immune response. In this study, we immobilize an in-house–designed peptide, KLLLRLRKLLRR (KLR), using a 2-step functionalization strategy onto stainless steel (SS) surfaces. SS is amino-silanized using (3-aminopropyl) triethoxysilane followed by tethering of KLR on it via formation of the amide bond. KLR-coated SS surfaces show nearly 95–100% reduction in bacterial colonization in vitro as obtained from antibacterial susceptibility testing while being non-toxic to mammalian cells. The coating strategy does not affect the microstructure of the SS surfaces. These findings demonstrate that this tethering process is able to produce excellent antibacterial surfaces.