title: NIR- and FRET-based sensing of Cu2+ and S2- in physiological conditions and in live cells.
abstract: We have synthesized a new indole functionalized rhodamine derivative L(1) which specifically binds to Cu(2+) in the presence of large excess of other competing ions with visually observable changes in their electronic and fluorescence spectral behavior. These spectral changes are significant enough in the NIR and visible region of the spectrum and thus enable naked eye detection. The receptor, L(1), could be employed as a resonance energy transfer (RET) based sensor for detection of Cu(2+) based on the process involving the donor indole and the acceptor Cu(2+) bound xanthene fragment. Studies reveal that L(1)-Cu complex is selectively and fully reversible in presence of sulfide anions. Further, fluorescence microscopic studies confirmed that the reagent L(1) could also be used as an imaging probe for detection of uptake of these ions in HeLa cells.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Guwahati, Assam, 781 039, India.
authors.forename: Chirantan
authors.initials: C
authors.lastname: Kar
authors.forename: Manab Deb
authors.initials: MD
authors.lastname: Adhikari
authors.forename: Aiyagari
authors.initials: A
authors.lastname: Ramesh
authors.forename: Gopal
authors.initials: G
authors.lastname: Das
mesh_terms: D000838:Anions; D001681:Biological Assay; D002470:Cell Survival / Q000187:drug effects; D056831:Coordination Complexes / Q000737:chemistry / Q000494:pharmacology; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D006367:HeLa Cells; D006801:Humans; D006834:Hydrazines / Q000737:chemistry; D008024:Ligands; D015394:Molecular Structure; D012235:Rhodamines / Q000737:chemistry*; D019265:Spectroscopy, Near-Infrared / Q000379:methods; D013440:Sulfides / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000838:Anions; D056831:Coordination Complexes; D005456:Fluorescent Dyes; D006834:Hydrazines; D008024:Ligands; D012235:Rhodamines; D013440:Sulfides; C029424:hydrazine; D003300:Copper