A new selective fluorescent chemical sensor for Fe3+ based on rhodamine B and a 1,4,7,10-tetraoxa-13-azacyclopentadecane conjugate and its imaging in living cells

A novel rhodamine B-based sensor 1 consisting of a rhodamine B moiety linked to the amine end of a 1,4,7,10-tetraoxa-13-azacyclopentadecane was designed and synthesized. Sensor 1 exhibits a high selectivity for Fe3+ in the presence of many other metal cations in a MeOH/H2O (1:1, v/v, pH = 7.4) solution. The binding analysis using a Job plot suggested that sensor 1 formed a 1:1 complex with Fe3+. The Fe3+ binding ability of 1 was further demonstrated by DFT calculations. Fluorescence microscopy experiments demonstrated that sensor 1 can be used as a fluorescent probe for the detection of Fe3+ in human liver cells (L-02) and rat neuronal cells (PC12). (C) 2014 Elsevier B.V. All rights reserved.