A facile sequentially-activatable fluorescent probe for fast imaging of the superoxide anion in ulcerative colitis.

Herein, a sequentially-activatable fluorescent probe, PT-3F, is engineered for fast fluorescence imaging of superoxide anion (O2˙-) under alkaline conditions. The synthesized probe displays high selectivity, minimal background interference and rapid response to O2˙-, enabling in vivo fluorescence imaging of O2˙- in PC-12 cells and colons of mice with ulcerative colitis (UC).