Dimeric BODIPY-loaded liposomes for dual hypoxia marker imaging and activatable photodynamic therapy against tumors

This work reports a dimeric BODIPY (BDP)-loaded liposome with conjugation of anti-HIF antibodies for dual hypoxia marker imaging and nitroreductase (NTR)-activatable photodynamic therapy (PDT) against hypoxic tumors. In this theranostic nanosystem (designated Ab-DiBDP NPs), the newly designed orthogonal BDP dimer has high O-1(2) quantum yield, and the substitution of a nitro group at the meso-position leads to the NTR-controllable activation of phototoxicity and fluorescence. Both in vivo and in vitro experiments demonstrate that the NTR-activatable PDT liposome can efficiently destroy cancer cells and prevent damage to normal cells. More significantly, the fascinating advantage of the nanoprobe is the synergy between the Cy 7-marked anti-HIF-1 antibody and the NTR-activatable DiBDP, which significantly improves the accuracy of tumor hypoxia imaging by simultaneous detection of NTR and HIF-1. Therefore, this work presents a new paradigm for NTR-triggered PDT against cancer cells and provides a new avenue for precise tumor hypoxia diagnosis.