A new rosamine-based fluorescent probe (RosCHO) for bisulfite was obtained by one pot reaction of p-phthalaldehyde and 3-(diethylamino)phenol, which showed excellent selectivity, high sensitivity and a rapid response toward bisulfite in aqueous solution. Upon the addition of HSO3−, the aldehyde moiety in probe RosCHO formed a hydrogen sulfite-dependent adduct product, leading to fluorescence enhancement due to the different ICT process. The detection limit for bisulfite was as low as 7 × 10−8 M, and fluorescence imaging of bisulfite in MCF-7 cells demonstrated its value to practical application in biological systems.
