Recent advances in coupling light-harvesting microorganisms with electronic components have led to a new generation of biohybrid devices based on microbial photocatalysts.These devices are limited by the poorly conduc...Recent advances in coupling light-harvesting microorganisms with electronic components have led to a new generation of biohybrid devices based on microbial photocatalysts.These devices are limited by the poorly conductive interface between phototrophs and synthetic materials that inhibit charge transfer.This study focuses on overcoming this bottleneck through the metabolically-driven encapsulation of photosynthetic cells with a bio-inspired conductive polymer.Cells of the purple non sulfur bacterium Rhodobacter sphaeroides were coated with a polydopamine(PDA)nanoparticle layer via the self-polymerization of dopamine under anaerobic conditions.The treated cells show preserved light absorption of the photosynthetic pigments in the presence of dopamine concentrations ranging between 0.05–3.5 mM.The thickness and nanoparticle formation of the membrane-associated PDA matrix were further shown to vary with the dopamine concentrations in this range.Compared to uncoated cells,the encapsulated cells show up to a 20-fold enhancement in transient photocurrent measurements under mediatorless conditions.The biologically synthesized PDA can thus act as a matrix for electronically coupling the light-harvesting metabolisms of cells with conductive surfaces.展开更多
基金funded by the Fonds National Suisse de la Recherche Scientifique,project Phosbury-Photosynthetic bacteria in Self-assembled Biocompatible coatings for the transduction of energy(Project Nr CRSII5_205925/1)M.G.acknowledges the funding from Fondazione CON IL SUD,Grant“Brains to South 2018”(project number 2018-PDR-00914).
文摘Recent advances in coupling light-harvesting microorganisms with electronic components have led to a new generation of biohybrid devices based on microbial photocatalysts.These devices are limited by the poorly conductive interface between phototrophs and synthetic materials that inhibit charge transfer.This study focuses on overcoming this bottleneck through the metabolically-driven encapsulation of photosynthetic cells with a bio-inspired conductive polymer.Cells of the purple non sulfur bacterium Rhodobacter sphaeroides were coated with a polydopamine(PDA)nanoparticle layer via the self-polymerization of dopamine under anaerobic conditions.The treated cells show preserved light absorption of the photosynthetic pigments in the presence of dopamine concentrations ranging between 0.05–3.5 mM.The thickness and nanoparticle formation of the membrane-associated PDA matrix were further shown to vary with the dopamine concentrations in this range.Compared to uncoated cells,the encapsulated cells show up to a 20-fold enhancement in transient photocurrent measurements under mediatorless conditions.The biologically synthesized PDA can thus act as a matrix for electronically coupling the light-harvesting metabolisms of cells with conductive surfaces.