Visible light-responsive all-organic polyurethane antibacterial coatings using a polythiophene derivative

Visible light-responsive antimicrobial coatings are of importance for antibacterial applications owing to widespread multidrug-resistant infections. Herein, the photocatalytic disinfection performance of an all-organic poly[2,11′-thiophene-ethylene-thiophene-alt-(2,5-(3-carboxyl)-thiophene] (PTET-T-COOH)/polyurethane (PU) coating was synthesized and evaluated. The coating consists of both a protective PU layer and a photoactive layer (PTET-T-COOH), which was prepared using isocyanate groups as linkers, then fabricated by drop-casting. The chemical linkage between PTET-T-COOH and NCO-terminated PU was researched based on ATR-FTIR and XPS analyses. The developed coating demonstrated good photocatalytic bactericidal performance on S. aureus under visible-light irradiation for 6 h. This study provided an effective platform for fabricating environmental-friendly and cheap antimicrobial surfaces.