Photogenerated Holes Mediated Nitric Oxide Production for Hypoxic Tumor Treatment

Nitric oxide (NO) is a gaseous signal molecule with multiple physiological functions, and it also plays a key role in cancer therapy. However, the production of NO which depends on O 2 or H 2 O 2 is limited within the tumor microenvironment, leading to unsatisfactory anticancer effect. Herein, we report a NO-based phototherapeutic strategy mediated by photogenerated holes for hypoxic tumors, which is achieved by irradiation of the poly-L-arginine modified carbon-dots-doped graphitic carbon nitride nanomaterial (ArgCCN). Upon red light irradiation, the photogenerated holes on ArgCCN oxidized water into H 2 O 2 which subsequently oxidized the arginine residues to produce NO. In vitro and in vivo experiments showed that the high concentration of NO produced by ArgCCN could induce cancer cell apoptosis. The presented phototherapeutic strategy is based on microenvironment-independent photogenerated holes mediated oxidation reaction, paving the way for the development of NO therapeutic strategy.