Dual‐acceptor engineering of donor‐acceptor type molecules for all‐round boosting anti‐tumor phototherapy

Abstract The integration of robust photon‐absorption capacity, high reactive oxygen species yields and photothermal conversion efficiency (PCE) into a single phototheranostic nano‐agents is ideal but rarely reported. This study employed a dual‐acceptor engineering strategy utilizing isoindigo and selenium‐substituted [1,2,5]thiadiazolo[3,4‐ c ]pyridine to augment the molar extinction coefficient and spin‐orbit coupling effect, respectively, resulting in a substantial enhancement of photon‐absorption ability and non‐radiative decay energy‐release process of donor‐acceptor type phototherapy molecules. As the optimal phototherapy agent, IID‐PSe exhibited a high molar extinction coefficient two times that of photosensitizer, excellent 1 O 2 yield (15%) and PCE (34%), exhibiting great potential for phototherapy. After encapsulating with DSPE‐PEG2000, IID‐PSe NPs showed excellent anti‐tumor phototherapy ability both in vitro and in vivo. This work provides an effective idea for designing high‐performance photosensitive dyes with high efficiency phototherapy output.