Biocompatible hypocrellin A-Fe(III) nanoparticles exhibiting efficient photo-activated CDT in vitro and in vivo.

Chemodynamic therapy (CDT) is novel and promising for cancer treatment, however, the potential systematic toxicity of the used nanoparticles is still a big concern. In this work the biocompatible hypocrellin A-Fe(III) nanoparticles (HA-Fe(III) NPs) were synthesized and studied. The CDT effect of HA-Fe(III) NPs in the dark is negligible but can be photo-activated upon red light irradiation, which is meaningful to realize precise CDT treatment by selective light irradiation. Moreover, HA-Fe(III) NPs can also generate O2˙-, which may be converted into H2O2 to further enhance the CDT effect. As a result, HA-Fe(III) NPs had little cytotoxicity in the dark at the concentration up to 200 µg ml-1, but exhibited efficient CDT activity upon red light irradiation under both normoxic and hypoxic conditions. The in vivo results also showed that HA-Fe(III) NPs can efficiently inhibit tumor growth upon 628 nm light irradiation.