A new rhodamine-based colorimetric chemosensor for naked-eye detection of Cue2+ in aqueous solution

A new colorimetric probe 1 based on rhodamine B lactam was developed for naked-eye detection of Cu2+. The optical feature of 1 for Cu2+ was investigated by UV-vis absorption spectroscopy. Upon the addition of Cu2+, the 1 displayed a distinct color change from colorless to pink, which can be directly detected by the naked eye. The stoichiometry of 1 to Cu2+ complex was found to be 1:1 and the naked-eye detection limit was determined as low as 2 mu M. The results suggest that the probe 1 may provide a convenient method for visual detection of Cu2+ with high sensitivity. 2015 Elsevier B.V. All rights reserved.