Efficient combined near-infrared-triggered therapy: Phototherapy over chemotherapy in chitosan-reduced graphene oxide-IR820 dye-doxorubicin nanoplatforms.

Significant efforts are currently being funneled into the improvement of therapeutic outcomes in cancer by designing hybrid nanomaterials that synergistically combine chemotherapeutic abilities and near-infrared (NIR) light-activated photothermal (PTT) and photodynamic (PDT) activity. Herein, a nanotherapeutic platform is specifically designed to integrate combinational functionalities: chemotherapy, PTT, PDT and traceable optical properties. The system, based on chitosan-reduced graphene oxide (chit-rGO), incorporates and carries a large payload of IR820 dye with dual PTT and PDT activity and a chemotherapeutic drug, doxorubicin (DOX). The potential of the fabricated nanoplatforms to operate as an NIR activatable therapeutic agent is first assessed in aqueous solution by investigating its ability to generate singlet oxygen and heat under NIR irradiation with 785 nm laser irradiation. The in vitro anticancer activity of chit-rGO-IR820-DOX is evaluated against murine colon carcinoma cells (C26). The fabricated nanosystem exhibits synergistic anticancer activity against C26 cancer cells by combining IR820 induced PDT, simultaneous graphene and IR820 induced PTT and the chemotherapeutic effect of DOX. Notably, the therapeutic performance of chit-rGO-IR820-DOX can be controlled by the ratio between IR820 and DOX. Moreover, chit-rGO-IR820-DOX facilitates localization inside cancer cells correlated with the release of DOX via mapping by confocal Raman microscopy.