Photosensitive MRI biosensor for BCRP-Targeted uptake and light-induced inhibition of tumor cells.

Riboflavin and its derivatives are the most important coenzymes in vivo metabolism, and are closely related to life activities. In this paper, the first photolysis 129Xe biosensor was developed by combining cryptophane-A with riboflavin moiety, which showed photosensitivity recorded by hyperpolarized 129Xe NMR/MRI technology with an obvious chemical shift change of 5.3 ppm in aqueous solution. Cellular fluorescence imaging confirmed that the biosensor could be enriched in MCF-7 cells, and MTT assays confirmed that the cytotoxicity was enhanced after irradiation. Findings suggested that the biosensor has a potential application in tumor targeting and the inhibition of tumor cell proliferation after photodegradation.