Protonation Regulates the Triplet State Decay of 6-Thioguanosine

Abstract

The long-lived triplet state of thionucleobases is shortened by the sugar moiety incorporation and self-quenching, limiting photochemical applications. We find that protonation significantly extends the triplet lifetime of 6-thioguanosine by increasing the intrinsic lifetime and reducing the self-quenching constant, offering new opportunities for thionucleoside-based photosensitizers and photoprobes.