A fluorescent probe strategy for the detection and discrimination of hydrogen peroxide and peroxynitrite in cells.

Aryl boronate fluorescent probes allow the non-invasive study of dynamic cellular processes involving the reactive species, hydrogen peroxide (H 2 O 2 ) and peroxynitrite (ONOO - ). However, the ability of these probes to differentiate between these two species remains unclear. Here, we report a boronate-functionalised hemicyanine dye (HD-BPin) as a potential strategy to distinguish between H 2 O 2 at 704 nm (red channel) and ONOO - at 460 nm (blue channel) in solution and in cells. This work also highlights the choice of fluorophore before boronate functionalization can dictate the observed selectivity between these two species.