Sensitive imaging of tumors using a nitroreductase-activated fluorescence probe in the NIR-II window

A nitroreductase (NTR)-activated NIR-II fluorescence probe for tumor imaging is reported. The probe can emit fluorescence in the range of 900-1300 nm, and target hypoxic tumors with NTR overexpression, thus allowing for accurate delineation of tumor margins through deep penetration.