Imaging dichromate in living cells with a fluorescence probe

Abstract The dichromate as an industrial oxidant has a very extensive application. However, as one of the heavy metal elements, chromium has become a great threat to the organism and environment due to its carcinogenicity and mutageicity. So far, there is only a small number of detection and imaging methods for dichromate. In this work, a new fluorescent probe RhoCr for detecting dichromate based on in situ Cr 3+ -controlled opening of spirolactam-ring in a rhodamine dye after Cr 2 O 7 2− reduced to Cr 3+ by NaHSO 3 in solution and self-reduction in organism is reported, which displays a strong enhancement of fluorescence emission (λ em 582 nm), fast response (completed within 2 min) and excellent sensitivity (DL 1.18 nM). RhoCr successfully obtained fluorescence images of the intracellular Cr 2 O 7 2− . In addition, the effect have been exhibited in tap water and pool water, which will be crucial to the detection of dichromate in the environment.