A Diode-Like Dye-Cu Anisotropic Junction in a Coordination Polymer as a Logic State Ratchet for Intratumor Redox Photomodulation

Redox logic materials offer new avenues to modulate intracellular pathologic redox environment area-specifically, but the unambiguity of redox logic states and their unidirectional and repetitive switchability are challenging to realize. By merging a bistable diisophthalic phenazine dye ligand with Cu-II salt, a multistable coordination polymer (CP) was constructed, of which the dye-Cu anisotropic junction achieved the diode-like unidirectional electron transfer and logic state ratchet for the first time. Radical cationic CP maintained OFF status with low toxicity in healthy tissues, but was reduced to the neutral SERVO state by the overexpressed glutathione (GSH) in hypoxic tumors. After photoirradiation, the stabilized charge-separated ON status promoted photo-Fenton reaction for reactive oxygen species (ROS) signal transduction, and simultaneously recovered the initial state for catalytic signal amplification of ROS, furnishing intratumor redox photomodulation for therapy.

Automated summary

Redox logic materials provide new approaches to modulate intracellular pathologic redox environment in specific areas, but the unambiguity and repetitive switchability of redox logic states are difficult to achieve. A multistable coordination polymer (CP) was constructed by combining a bistable diisophthalic phenazine dye ligand with Cu-II salt, and its dye-Cu anisotropic junction achieved diode-like unidirectional electron transfer and logic state ratchet for the first time. The radical cationic CP remained in the OFF state with low toxicity in healthy tissues, but was reduced to the neutral SERVO state by overexpressed glutathione (GSH) in hypoxic tumors. After photoirradiation, the stabilized charge-separated ON state promoted photo-Fenton reaction for reactive oxygen species (ROS) signal transduction, while simultaneously recovering the initial state for catalytic signal amplification of ROS, providing intratumor redox photomodulation for therapy.