title: Calix receptor edifice; scrupulous turn off fluorescent sensor for Fe(III), Co(II) and Cu(II).
abstract: Novel Supramolecular fluorescence receptor derived from calix-system i.e. calix[4]resorcinarene bearing dansylchloride as fluorophore was designed and synthesized. The compound was purified by column chromatography and characterized by elemental analysis, NMR and Mass spectroscopy. Tetradansylated calix[4] resorcinarene (TDCR) shows a boat conformation with C(2)v symmetry. The complexation behaviour of metal cations [Ag(I), Cd(II), Co(II), Fe(III), Hg(II), Cu(II), Pb(II), Zn(II), U(VI) (1 × 10(-4) M)] with tetra dansylated calix[4]resorcinarene (1 × 10(-6) M) was studied by spectophotometry and spectrofluorometry. Red shift in the absorption spectra led us to conclude that there is strong complexation Fe(III), Co(II) and Cu(II) with TDCR. These metal cations also produce quenching with red shifts in the emission spectra. The maximum quenching in emission intensity was observed in the case of Fe(III) and its binding constant was also found to be significantly higher than that of Co(II) and Cu(II). Quantum yield of metal complexes of Fe(III) was found to be lower in comparison with Co(II) and Cu(II) complexes. Stern Volmer analysis indicates that the mechanism of fluorescence quenching is either purely dynamic, or purely static.
authors: Department of Chemistry, School of Sciences, Gujarat University, Ahmedabad, India.
authors: Keyur D
authors: KD
authors: Bhatt
authors: Hrishikesh S
authors: HS
authors: Gupte
authors: Bharat A
authors: BA
authors: Makwana
authors: Disha J
authors: DJ
authors: Vyas
authors: Debdeep
authors: D
authors: Maity
authors: Vinod K
authors: VK
authors: Jain
mesh_terms: D000042:Absorption; D047250:Calixarenes / Q000138:chemical synthesis / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D003035:Cobalt / Q000032:analysis / Q000737:chemistry; D003300:Copper / Q000032:analysis / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D007501:Iron / Q000032:analysis / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: C506857:C-ethylcalix(4)resorcinarene; D005456:Fluorescent Dyes; D019216:Metals, Heavy; D009942:Organometallic Compounds; D047250:Calixarenes; D003035:Cobalt; D003300:Copper; D007501:Iron