title: Thiophene anchored coumarin derivative as a turn-on fluorescent probe for Cr3+: cell imaging and speciation studies.
abstract: A thiophene-coumarin hybrid molecule, (6E)-6-((thiophen-2-yl)methyleneamino)-2H-chromen-2-one (TMC) has been prepared and its single crystal X-ray structure is reported. TMC can selectively detect Cr(3+) in presence of other common cations. Both TMC and its Cr(3+) complex are well characterized by different spectroscopic techniques like (1)H NMR, QTOF-MS ES(+), FTIR and elemental analysis as well. TMC exhibits fluorescence enhancement upon binding Cr(3+) in CH(3)CN-HEPES buffer (0.02 M, pH 7.4) (4:6, v/v) medium. Detection limit of the method is 1 × 10(-6)M. Binding constant is estimated with the Benesi-Hildebrand method and the value 8 × 10(4) indicates a fairly strong interaction between TMC and Cr(3+). Speciation studies have been performed in a fast and environment friendly way using least sample volume, less hazardous chemicals and solvents. Cr(3+) assisted restricted rotation around the imine bond and inhibited photo-induced electron transfer from the N,S-donor sites to the coumarin unit are responsible for fluorescence enhancement. TMC is capable to detect intracellular Cr(3+) in living cells.
authors.affiliation: Department of Chemistry, The University of Burdwan, Burdwan, West Bengal, India.
authors.forename: Subarna
authors.initials: S
authors.lastname: Guha
authors.forename: Sisir
authors.initials: S
authors.lastname: Lohar
authors.forename: Arnab
authors.initials: A
authors.lastname: Banerjee
authors.forename: Animesh
authors.initials: A
authors.lastname: Sahana
authors.forename: Ipsit
authors.initials: I
authors.lastname: Hauli
authors.forename: Subhra Kanti
authors.initials: SK
authors.lastname: Mukherjee
authors.forename: Jesús Sanmartín
authors.initials: JS
authors.lastname: Matalobos
authors.forename: Debasis
authors.initials: D
authors.lastname: Das
mesh_terms: D002477:Cells; D002857:Chromium / Q000032:analysis*; D003374:Coumarins; D018360:Crystallography, X-Ray; D003584:Cytological Techniques / Q000379:methods*; D003952:Diagnostic Imaging / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D015394:Molecular Structure; D013876:Thiophenes
chemical_list: D003374:Coumarins; D005456:Fluorescent Dyes; D013876:Thiophenes; D002857:Chromium; C030123:coumarin