Rhodamine based fluorescent chemosensors for Hg 2+ and its biological application

Abstract

Two new chemosensors, rhodamine 6G derivative bearing hydroxyethyl group (1) and rhodamine base derivative bearing 15-crown-5 group (2) were synthesized and their sensing behaviors toward various metal ions were investigated by UV/Vis and fluorescence spectroscopies. Addition of Hg 2+ ion to a CH3CN solution of 1 and 2 gave visual color changes as well as fluorescent OFF-ON observations. Selectivity and sensitivity of 1 towards Hg 2+ are excellent enough to detect micromolar level of Hg 2+ ion, even in equeous media and biological sample (HeLa cell).