Two rhodamine based chemosensors for Sn4+ and the application in living cells

Two rhodamine based probes were designed and prepared for Sn4+ via opening of the spiro-ring to give fluorescent and colored species. The two probes exhibited a strong fluorescence enhancement upon addition of Sn4+ while showing almost no response to other cations in CH3CH2OH/HEPES buffer solution. Probe L1 exhibited fast selectivity toward Sn4+ and could be completed in 1 min. Fluorescence imaging experiments of Sn4+ in living MGC803 cells demonstrated its value of practical applications in biological systems.