Rhodamine-labelled new architecture for dual sensing of Co2+ and Hg2+ ions

A new rhodamine-based chemosensor 1 has been designed and synthesized. The receptor selectively recognizes Co2+ and Hg2+ ions in CH3CN/water (4:1, v/v; 10 μM tris HCl buffer, pH 6.8) by showing different extents of change in emission. The disappearance of colour of mercury-ensemble of 1 followed by appearance of distinct bluish colour under UV illumination upon addition of l-cysteine distinguishes Hg2+ from Co2+ ions. The receptor shows in vitro detection of both the ions in human cervical cancer (HeLa) cells.