Graphene@Curcumin-Copper Paintable Coatings for the Prevention of Nosocomial Microbial Infection

The rise of antimicrobial resistance has brought into focus the urgent need for the next generation of antimicrobial coating. Specifically, the coating of suitable antimicrobial nanomaterials on contact surfaces seems to be an effective method for the disinfection/contact killing of microorganisms. In this study, the antimicrobial coatings of graphene@curcumin-copper (GN@CR-Cu) were prepared using a chemical synthesis methodology. Thus, the prepared GN@CR-Cu slurry was successfully coated on different contact surfaces, and subsequently, the GO in the composite was reduced to graphene (GN) by low-temperature heating/sunlight exposure. Scanning electron microscopy was used to characterize the coated GN@CR-Cu for the coating properties, X-ray photon scattering were used for structural characterization and material confirmation. From the morphological analysis, it was seen that CR and Cu were uniformly distributed throughout the GN network. The nanocomposite coating showed antimicrobial properties by contact-killing mechanisms, which was confirmed by zone inhibition and scanning electron microscopy. The materials showed maximum antibacterial activity against E. coli (24 ± 0.50 mm) followed by P. aeruginosa (18 ± 0.25 mm) at 25 µg/mL spot inoculation on the solid media plate, and a similar trend was observed in the minimum inhibition concentration (80 µg/mL) and bactericidal concentration (160 µg/mL) in liquid media. The synthesized materials showed excellent activity against E. coli and P. aeruginosa. These materials, when coated on different contact surfaces such medical devices, might significantly reduce the risk of nosocomial infection.