Tracking Light-Induced Electron Transfer Towards O ₂ in a Hybrid Photoredox-Laccase System

Photobiocatalysis is an interesting approach to use light perform specific chemical transformations in a selective and efficient way. The intention couple photoredox cycle with enzyme performing multielectronic catalytic activity. Laccase, robust multicopper oxidase, can be envisioned as tool dioxygen clean electron sink when coupled oxidation photocatalyst. Here, we provide detailed study of the coupling [Ru(bpy)3]2+ photosensitizer laccase. We demonstrate that laccase reduction requires using relay like methyl viologen. In presence dioxygen, electrons transiently stored superoxide ions (O2●–) are scavenged by leading formation water instead H2O2. net result photo accumulation, essentially irreversible way, highly oxidizing [Ru(bpy)3]3+. This provides global scheme for future laccase, tandem light-driven oxidative process, O2 both one-electron transfer 4-electron substrate become sustainable final acceptor such hybrid photocatalytic process.