A Nanowire-Based Flexible Antibacterial Surface Reduces the Viability of Drug-Resistant Nosocomial Pathogens

Abstract

The global emergence of antimicrobial resistance poses a serious risk to patients by increasing the cost of healthcare with prolonged stay in hospitals, serious clinical complications, and even death. The ever-increasing challenges in discovering antibacterial agents with novel mechanisms of action necessitates the development of smart antibacterial surfaces that have the potential to minimize colonization of common hospital surfaces with bacterial pathogens. In this work, we report the antibacterial properties of flexible poly(dimethylsiloxane) (PDMS) polymer decorated with copper hydroxide nanowires (PDMS_Cu) against a panel of drug-resistant bacterial pathogens isolated from patients with bloodstream infection. The fabricated PDMS_Cu surface showed superior antimicrobial activity against both Gram negative (Escherichia coli and Klebsiella pneumoniae) and Gram positive (Staphylococcus aureus) bacterial strains as compared to flat PDMS and glass coverslip, which were used as controls. RAW macrophage and HeLa cells were seeded on the PDMS_Cu surface. Their viability was evaluated using confocal microscopy and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. PDMS_Cu surface supported the viability of both RAW macrophages and HeLa cells post 5 h of incubation suggesting its potential application in a healthcare setting. Furthermore, we demonstrate the possibility of employing a thin film of PDMS_Cu surface as a protective covering over the microphone of a digital stethoscope to prevent the transmission of nosocomial pathogens between patients. In addition, this fabrication technique was used to coat commercially available gloves with a thin layer of PDMS_Cu, which can be used in a hospital setting to curtail the spread of nosocomial infections while handling infectious instruments and surfaces.