Abstract
Transformations of chemodosimeter in its various chemical environments.
•Two probes have been prepared and characterized by IR, 1H NMR, 13C NMR and ESI-MS.•Highly selective and sensitive chemosensor towards Cr3+ ions over other metal ions.•1:1 stoichiometry of probe to Cr3+ was confirmed by ESI-MS.•Exhibited a good binding constant and lowest detection limit towards Cr(III).•Serves as reversible chemosensor for Cr3+ by using a strong chelator such as EDTA.
Two novel fluorescent rhodamine derivatives L1 and L2 have been synthesized and characterized by various analytical techniques. The sensors exhibited an extremely selective and sensitive “turn-ON” fluorescent and colorimetric response toward Cr3+ in methanol. Upon the addition of Cr3+, the spirolactam ring of probes was opened and a 1:1 metal–ligand complex was formed. The stoichiometry between Cr3+ and probe was further clarified by mass spectra. The chemodosimeter (L1 and L2) exhibited a good binding constant and lowest detection limit towards Cr(III), and also successfully examined the reversibility of complexation of metal to ligand (opened ring to spirolactam ring).