pH-sensitive nanomedicine based on PEGylated nanodiamond for enhanced tumor therapy

Enhancing chemotherapeutic efficiency through enriched drug load and controlled drug release is urgent for alleviating the suffering of cancer patients. Here, a novel pH-sensitive nanomedicine was constructed to acquire high drug loading capacity and better therapeutic efficiency. Interestingly, with the assistance of a pH 8.0 sodium borate buffer solution, PEGylated nanodiamond vehicles loaded with doxorubicin (DOX) achieved nearly 50% loading efficiency, low premature drug release in physiological conditions and effective stimuli-response release under a tumor microenvironment. In addition, assessment by flow cytometry and cell migration assay illustrated that NP/D could induce cell apoptosis, cycle abnormality and inhibit cell migration. The results from the confocal fluorescence microscopy study showed that NP/D could be internalized into cells and distributed into the cytoplasm, subsequently DOX detaches from NP/D and could migrate and enter the nucleus to inhibit cell proliferation. NP/D can open the window for new nanodrugs for a broad spectrum of anticancer agents.