title: Pyrophosphate sensing by a fluorescent Zn2+ bound triazole linked imino-thiophenyl conjugate of calix[4]arene in HEPES buffer medium: spectroscopy, microscopy, and cellular studies.
abstract: An in situ prepared Zn(2+) complex of triazole linked imino-thiophenyl conjugate of calix[4]arene, [ZnL], was demonstrated to be highly fluorescent in HEPES buffer solution. [ZnL] has been used as a chemo-sensing ensemble for the recognition of phosphates in general and pyrophosphates in particular among the eighteen different anions studied. The chemo-sensing behavior of the [ZnL] has been demonstrated through fluorescence, absorption, visual fluorescent color changes, ESI MS, and (1)H NMR titrations. Variations in the microstructural features of L, its zinc complex and the complex upon addition of PPi have been demonstrated through atomic force microscopy and transmission electron microscopy. Such studies have been extended to see the permeability of the conjugate into the HeLa cells by fluorescence microscopy. In accession, a reversible "write-read-erase-read" logic gate property of L has been demonstrated through a feedback loop in the presence of Zn(2+) and PPi.
authors.affiliation: Bioinorganic Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India.
authors.forename: Rakesh K
authors.initials: RK
authors.lastname: Pathak
authors.forename: Khatija
authors.initials: K
authors.lastname: Tabbasum
authors.forename: Ankit
authors.initials: A
authors.lastname: Rai
authors.forename: Dulal
authors.initials: D
authors.lastname: Panda
authors.forename: Chebrolu P
authors.initials: CP
authors.lastname: Rao
mesh_terms: D002021:Buffers; D047250:Calixarenes / Q000737:chemistry*; D011756:Diphosphates / Q000032:analysis*; D005456:Fluorescent Dyes; D006531:HEPES; D006367:HeLa Cells; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008853:Microscopy; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D013050:Spectrometry, Fluorescence; D021241:Spectrometry, Mass, Electrospray Ionization; D013439:Sulfhydryl Reagents / Q000737:chemistry; D014230:Triazoles / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D002021:Buffers; D011756:Diphosphates; D005456:Fluorescent Dyes; D013439:Sulfhydryl Reagents; D014230:Triazoles; D047250:Calixarenes; D015032:Zinc; D006531:HEPES