An Oxidative Stress Amplified Antibacterial S-SEBS@CuLM Coating with Synergistic ROS Scavenging Inhibition

Abstract

As reactive oxygen species (ROS) can induce oxidative stress in bacteria and eliminate them without promoting bacterial drug resistance, ROS-based antibacterial strategies have garnered significant attention in recent years. However, bacteria possess a range of antioxidant mechanisms to counteract the bactericidal effects of ROS. Consequently, in this study, we developed an antibacterial surface based on Ga3+-enhanced ROS antibacterial efficacy. This surface consists of a superhydrophobic material sequentially modified with gallium-based liquid metal (GLM) and Cu2+. It is noteworthy that the increased H2O2 in the bacterial microenvironment enables Cu2+ to produce reactive oxygen species through catalyzing electron transfer in the Fenton reactions to achieve bactericidal effect. Meanwhile, the simultaneous use of Ga3+ and Cu2+ to destroy the bacterial redox process and inhibit its basic function further enhances antimicrobial properties. Results show that this superhydrophobic coating prevents bacterial adhesion and growth while releasing Ga3+ and Cu2+ for sustained bactericidal activity. The antimicrobial rate exceeds 99.99% against Escherichia coli and Staphylococcus aureus. In addition, the coating also exhibits excellent in vitro biocompatibility. This work provides a novel and effective strategy for developing antimicrobial surfaces for biomedical materials.

Keywords: Antibacterial coating, Reactive oxygen species, Ga3+ and Cu2+, Destruction of redox process