Chemo-photodynamic therapeutics can function synergistically[1].Moreover,photodynamic therapy could be enhanced by a sequential release protocol[2].In our study,the sequential release of photosensitizer MB was realized by introducingbig & small combo self-decomposable NPs system,which could improve the chemo therapeutic efficacy of antitumor drug gemcitabine hydrochloride (GM·HCl) by long duration P-gp inhibition (Fig.1).