A Stimulated Mixed Micelle System for In Vitro Study on Chemo-Photodynamic Therapy

A mixed micelle system with pH-responsive and photoactive zinc tetra(progaryloxy-phenyl) porphyrin (ZnTPP) core is constructed for encapsulation of doxorubicin (DOX) to facilitate combined chemo-photodynamic therapy in one delivery system. The mixed micelles show low critical micelle concentration, good storage stability, a pH dependent behavior, and better singlet oxygen generation efficiency compared to the star-shaped PEG-ZnTPP micelles, where the aggregation of ZnTPP within the core, resulting in less photoactive effect. The cell viability treated with DOX-loaded mixed micelles shows higher cytotoxicity than single drug loaded micelles under light irradiation. The improved therapeutic efficiency indicates the combined effect of DOX and ZnTPP and this mixed micelle system has potential as dual-modality for cancer treatment.