A mitochondria-targeted near infrared ratiometric fluorescent probe for the detection of sulfite in aqueous and in living cells

A compound YSP, absorbs (597 nm) and emits (681 nm) in red wavelength region, was synthesized and served as mitochondria-targeted ratiometric fluorescent probe for sulfite. The probe responded to sulfite quickly through a two-step process, which was confirmed by the NMR titration.197