Oxidative burst as a continuous H2O2 supplier for tumor oxygenation in photodynamic therapy

Abstract

Catalyzing H₂O₂ decomposition to generate O₂ can relieve tumor hypoxia, but the insufficient content of endogenous H₂O₂ limits its effect. Here, a nanomedicine consisting of Fe₃O₄ and zinc phthalocyanine (ZnPc12) was fabricated. In the tumor's normoxia zone, the photodynamic therapy (PDT) effect of ZnPc12 induces cancer cell's oxidative burst to generate massive endogenous H₂O₂. Fe₃O₄ catalyzes H₂O₂ decomposition to generate sufficient O₂ for PDT in the nearby hypoxia zone. It is the first time to utilize oxidative burst as a continuous H₂O₂ self-supplier for cancer treatment.