Photothermally Activated Coacervate Model Protocells as Signal Transducers Endow Mammalian Cells with Light Sensitivity

The development of a novel photothermally activated coacervate model protocell is reported as a signal transducer to endow mammalian cells with light sensitivity. In this system, near-infrared light irradiation triggers H2 S release in coacervate model protocells, leading to modulation of the behavior of living cells. The functional coacervate model protocells are prepared by loading metal-alloyed plasmonic nanoparticles and an H2 S donor into the liquid coacervate microdroplets. Upon light irradiation, the H2 S signal messenger is released through the photothermal effect of plasmonic nanoparticles and photothermal mediated pyrolysis of the H2 S donor. The H2 S signal is delivered to the mammalian cell community to trigger depletion of reactive oxygen species, reduce the activity of lactate dehydrogenase and improve cell viability. This study provides a new approach to the implementation of chemical signaling in artificial cell colonies and protocell/living cell consortia. The photothermal protocell system offers a powerful platform for light modulation of the behavior of mammalian cells and shows great promise for biomedical applications.