Selective dual-mode detection of reactive oxygen species and metal ions by chemodosimetric vs. chelation pathways: fluorescence turn-on with OCl? and Zn2+/Mn2+, employing theoretical, practical, and bioimaging applications
An indole-coupled diaminomaleonitrile-based fluorescent chemosensor IMA has been designed and developed for the selective detection of ROS (OCl?) and metal ions Zn2+ and Mn2+via chemodosimetric and chelation pathways respectively. The selective sensing of OCl? is induced by a method of oxidatively cleaving of the imine bond of IMA, forming free indole aldehyde, which results in a 21-fold enhancement of fluorescence at 521 nm, with a detection limit of 2.8 M. On the other hand, the selective binding of IMA with Zn2+ and Mn2+ results in chelation-induced enhanced fluorescence (CHEF) and increased intermolecular charge transfer (ICT), leading to a 4-fold and 3-fold fluorescence enhancement at 432 nm and 435 nm, with the detection limits of 12.71 M and 17.34 M, respectively. UV-vis spectroscopy, fluorescence, DFT study, mass spectra, 1H-NMR analysis, and Job's plot analysis have been used to validate the sensing mechanism of IMA with OCl?, Zn2+, and Mn2+. For practical applications, the binding of IMA with OCl? has been utilized in the detection of commercial samples like bleaching powder and water analysis. Bio-imaging studies were conducted with IMA in the presence of OCl? and Zn2+ using green gram seeds in a physiological medium. 2025 The Royal Society of Chemistry.
Kumar, Malavika S.; Das, Avijit Kumar; Bylappa, Yatheesharadhya; Nag, Anish
RSC Advances;Volume;15;Issue;9;pp.6708-6717
All Open Access; Gold Open Access; Green Open Access
https://doi.org/10.1039/d4ra08191a https://www.scopus.com/pages/publications/105000023924?origin=resultslist
Kumar M.S., Department of Chemistry, Christ University, Hosur Road, Karnataka, Bangalore, 560029, India; Das A.K., Department of Chemistry, Christ University, Hosur Road, Karnataka, Bangalore, 560029, India; Bylappa Y., Department of Life Science, Christ University, Hosur Road, Karnataka, Bangalore, 560029, India; Nag A., Department of Life Science, Christ University, Hosur Road, Karnataka, Bangalore, 560029, India