Functionalized MoS2-nanosheets for targeted drug delivery and chemo-photothermal therapy.

Molybdenum disulfide (MoS2) has been extensively explored for biomedical applications due to its excellent photothermal conversion ability. In this paper, we report a nanoplatform based on folic acid (FA) targeted dual-stimuli responsive MoS2 nanosheets and explore this for the treatment of FA-receptor positive human breast cancer. The nanocomposites generated had a uniform diameter (ca. 133 nm), and could be loaded with the anti-cancer drug doxorubicin (DOX) to a high capacity (151.4 mg/g). The release of DOX was greatly accelerated at pH 5.0 as compared to pH 7.4. In addition, it was found that drug release is enhanced under near infrared laser (NIR) irradiation, showing that the composites can be used as dual responsive systems, with DOX release controllable through pH or NIR irradiation. MTT assays and confocal experiments showed that the MoS2-based nanoplatform could selectively target and kill FA-positive MDA-MB-231 cells (a human breast cancer cell line). The platform also allowed the combination of chemotherapy and photothermal therapy, which led to synergistic effects superior to either monotherapy. The functionalized MoS2 nanoplatform developed in this work hence could be a potent system for targeted drug delivery and synergistic chemo-photothermal cancer therapy.