Target-Binding Accelerated Response for Sensitive Detection of Basal H₂O₂ in Tumor Cells and Tissues via a Dual-Functional Fluorescence Probe

Abstract

Aberrant production of H₂O₂ is involved in cancer. The levels of H₂O₂ are significantly higher in tumor cells than in normal cells. It is important to develop fluorescent probes to image basal H₂O₂ selectively in tumor cells. So far, a cancer cell-targeting probe to image basal H₂O₂ has not been reported. Thus, we developed a fluorescent probe, <b>BBHP</b>, which contains benzil as a H₂O₂-recognition site and biotin as a target binding motif for the selective and sufficient detection of H₂O₂ in tumor cells. <b>BBHP</b> enables a selective fluorescence turn-on response to H₂O₂. The binding of the probe with biotin receptors can greatly accelerate the fluorescence response to H₂O₂. As a result, <b>BBHP</b> can sufficiently image basal H₂O₂ in biotin receptor-positive cancer cells and tumor tissues. Finally, <b>BBHP</b> was successfully applied to discriminate between cancerous and normal tissues.