Fluorescent intracellular imaging of reactive oxygen species and pH levels moderated by a hydrogenase mimic in living cells.

The catalytic generation of H in living cells provides a method for antioxidant therapy. In this study, an [FeFe]-hydrogenase mimic [Ru + FeS@F127(80)] was synthesized by self-assembling polymeric pluronic F-127, catalytic [FeS] sites, and photosensitizer Ru(bpy) . Under blue light irradiation, hydrated protons were photochemically reduced to H, which increased the local pH in living cells (HeLa cells). The generated H was subsequently used as an antioxidant to decrease reactive oxygen species (ROS) levels in living cells (HEK 293T, HepG2, MCF-7, and HeLa cells). Our findings revealed that the proliferation of HEK 293T cells increased by a factor of about six times, relative to that of other cells (HepG2, MCF-7, and HeLa cells). Intracellular ROS and pH levels were then monitored using fluorescent cell imaging. Our study showed that cell imaging can be used to evaluate the ability of Ru + FeS@F127 to eliminate oxidative stress and prevent ROS-related diseases.