Fluorescent nanoprobe for in-vivo ratiometric imaging of endogenous hydrogen peroxide resulted from drug-induced organ damages

Drug-induced organ damages have been considered as a grave problem regarding public health; hence effective method for in vivo detection of drug-induced organ damages is of great significance. Herein we developed a ratiometric fluorescent nanoprobe (NPs-A), which was prepared by loading the probe molecules into phospholipid bilayer, for assaying hydrogen peroxide (H 2 O 2 , an organ damage biomarker) level in vivo. The photophysical behavior of the probe molecule depends on the electron-withdrawing ability of the group at the 6- position of anthracene ring, on which the recognition moiety for hydrogen peroxide (dicarbonyl coupled with nitrophenyl, referred to as nitrophenyl-dicarbonyl) was introduced. Upon the reaction of the probe with H 2 O 2 , nitrophenyl-dicarbonyl group transforms into carboxyl group, and due to the variation of the electron-withdrawing ability of the 6th substituent , the fluorescent properties of the probe molecule alters accordingly, thus ensuring the ratiometric detection for H 2 O 2 with high selectivity with the detection limit of 0.49   μM. In addition, the nanoprobe (NPs-A) was applied for cell and in vivo imaging applications; and the results indicate that it can detect and track the level of H 2 O 2 in living cells and to monitor and spatially map endogenous H 2 O 2 levels in a drug-induced organ damage model of zebrafish.