Ultra-high payload of doxorubicin and pH-responsive drug release in CuS nanocages for a combination of chemotherapy and photothermal therapy

A novel versatile system combining chemotherapy and photothermal therapy for cancer cells using CuS NCs is reported. CuS NCs were synthesized by a solid-liquid reaction between Cu2O nanocubes and thiourea. While the hollow nanocage can be used to load anticancer drugs for chemotherapy, the CuS can convert NIR light into heat for photothermal therapy. More importantly, CuS NCs display exceptionally high drug loading capacity of DOX with 500 wt% and release of DOX is pH-controllable, which is a spontaneous process under intracellular conditions. Compared with chemotherapy or photothermal therapy alone, the combination of chemotherapy and phototherapy can significantly improve the therapeutic efficacy. This improvement strategy using multifunctional nanomaterials may be particularly useful in biomedical applications.