Near-Infrared Fluorescent Probe Activated by Nitroreductase for and Hypoxic Tumor Detection.

Tumor hypoxia is correlated with increased resistance to chemotherapy and poor overall prognoses across a number of cancer types. We present here a cancer cell-selective and hypoxia-responsive probe () designed on the basis of density functional theory (DFT)-optimized quantum chemical calculations. The probe was found to provide a rapid fluorescence "off-on" response to hypoxia relative to controls, which lack the folate or nitro-benzyl moieties. confocal microscopy and flow cytometry analyses, as well as near-infrared optical imaging of CT26 solid tumor-bearing mice, provided support for the contention that is more readily accepted by folate receptor-positive CT26 cancer cells and provides a superior fluorescence "off-on" signal under hypoxic conditions than the controls. Based on the findings of this study, we propose that may serve as a tumor-targeting, hypoxia-activatable probe that allows for direct cancer monitoring both and .