After loaded with probe FHZ and treated with HClO and H ₂ O ₂ /EDTA-Fe ²⁺ in order, HeLa cells display the bright fluorescences from both cyan and green channels. FHZ can give out two different fluorescent signals in the presence of both ?OH and HClO, suggesting the synchronous discrimination of ?OH and HClO by a dual-channel detection model with two exciting wavelengths. Probe FHZ shows very high specificity to the detections of ?OH and HClO with the excitations at 410 and 490 nm, respectively. The probe FHZ can efficiently enter the cellular mitochondria and exhibit the differentiable/visual capabilities to the endogenous ?OH and HClO by the dual fluorescent responses.

Probe FHZ can rapidly be absorbed into the blood circulation system from the zebrafish intestine, and spread out whole zebrafish tissues, and keep its stability in the blood, organs and tissues in the absence of ROS. The probe can keep its stability in biological environments and only selectively react with ?OH and HClO species.