Bakiyalakshmi G. and Selvanathan G.
Abstract
A stimuli-responsive highly functionalized heterocyclic chemosensor was developed for dual colorimetric and fluorescence sensing of metal ions in aqueous media. The chemosensor was synthesized via a diazo coupling reaction and characterized by FT-IR, ^1H NMR, and ^13C NMR spectroscopy. Its optical sensing performance was investigated using UVâVisible and fluorescence spectroscopy toward various metal ions. The chemosensor exhibited distinct colorimetric and fluorescence responses with high selectivity toward target metal ions, accompanied by significant changes in absorption and emission characteristics upon complex formation. Binding interactions were evaluated by spectrophotometric titration and Jobâs plot analysis, confirming stable chemosensorâmetal ion complex formation. The practical applicability of the chemosensor was further demonstrated through fluorescence-based sensing and visual colorimetric detection in aqueous media. The developed chemosensor offers a simple, rapid, and cost-effective dual-mode sensing platform with potential applications in environmental monitoring and analytical chemistry.