A self-immolative near-infrared probe based on hemi-benzothiazolecyanine for visualizing hydrogen peroxide in living cells and mice

Hemicyanine dyes including hemi-indocyanine and hemi-benzindocyanine have been attracted considerable attentions to develop near infrared probes for in vivo fluorescence imaging. However, hemi-benzothiazolecyanine dye (MTR) is rarely reported for detection analytes. In this work, to extend the sensing applications of MTR, we present an optimized route for facile preparation of the dye. And as a proof-of-concept, a self-immolative NIR probe MTR-HH based on hemi-benzothiazolecyanine dye was designed and synthesized for H2O2. The probe exhibited a 284-fold fluorescent enhancement to H2O2 with a detection limit of 0.32 mu M over other biospecies. Moreover, MTR-HH was successfully applied for visualizing endogenous H2O2 in living cells and mice.

Automated summary

An optimized route was established for facile preparation of the hemi-benzothiazolecyanine dye MTR, and a self-immolative NIR probe MTR-HH was successfully designed and synthesized for detecting H2O2 with a remarkable 284-fold fluorescent enhancement. The probe showed great potential in visualizing endogenous H2O2 in living cells and mice.