LAUSR

Abstract Fe 3+ plays a crucial role in many vital cell functions and its detection has attracted considerable attention. In this work, a water-soluble rhodamine-based chemosensor RL has been designed and synthesized as an “off-on” chemosensor for Fe 3+ detection. Upon the addition of Fe 3+ , RL displayed obvious color change, quick fluorescence enhancement, high sensitivity and anti-interference capacity over other metal ions (Li + , Na + , K + , Mg 2+ , Ca 2+ , Ba 2+ , Al 3+ , Sn 2+ , Pb 2+ , Bi 3+ , Cr 3+ , Mn 2+ , Co 2+ , Ni 2+ , Pd 2+ , Cu 2+ , Ag + , Zn 2+ , Cd 2+ , Hg 2+ ). The detection limit for Fe 3+ was calculated to be 0.28 μM with the binding constant K a to be 4.67 × 10 8  M −2 . Furthermore, an application of RL in the imaging of HeLa cells exposed to Fe 3+ was also successfully demonstrated.