title: Multivalent calix[4]arene-based fluorescent sensor for detecting silver ions in aqueous media and physiological environment.
abstract: A new derivative of dipodal 1,3-calix[4]arene-based chemosensor (R), which was containing several binding sites have been synthesized and characterized by NMR, IR and LC-MS spectroscopic methods. The selectivity of Rhas been investigated in aqueous methanol, resulting in fluorescence shift and selective recognition of Ag+among 20 various alkali, alkaline earth and transition metal ions. Microstructural features of R and its complex with Ag+have been investigated by Atomic Force Microscopy (AFM). AFM images can clearly differentiate R from its complex of Ag+. Moreover; the complicated binding mode of metal-ligand complex has been explored by UV-Vis, LC-MS, FIR, Fluorescence titration, Job's plot method and theoretical approaches. Density functional theory (DFT) method at B3LYP/LANL2DZ level of theory was employed for computational studies. Theoretical calculations revealed that selectivity and specificity of R toward Ag+could be attributed to structural conformation of 1,3-alternate-calix[4]arene scaffold and molecular electrostatic potential of its surface. Furthermore; the competitive experiments were carried out to test sensor's ability for practical uses. Finally, the efficiency of R in matrix of physiological cations was examined and showed gradual emission enhancement which makes R an ideal candidate for monitoring of Ag+in physiological environment.
authors.affiliation: Faculty of Chemical Processes Development, Chemistry & Chemical Engineering Research Center of Iran (CCERCI), Tehran, Iran.
authors.forename: Behzad
authors.initials: B
authors.lastname: Lotfi
authors.affiliation: Faculty of Chemical Processes Development, Chemistry & Chemical Engineering Research Center of Iran (CCERCI), Tehran, Iran. Electronic address: Tarlani@ccerci.ac.ir.
authors.forename: Aliakbar
authors.initials: A
authors.lastname: Tarlani
authors.affiliation: Faculty of Modern Technologies, Chemistry & Chemical Engineering Research Center of Iran (CCERCI), Tehran, Iran.
authors.forename: Peyman
authors.initials: P
authors.lastname: Akbari-Moghaddam
authors.affiliation: Faculty of Modern Technologies, Chemistry & Chemical Engineering Research Center of Iran (CCERCI), Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Mirza-Aghayan
authors.affiliation: Physical Chemistry Department, Tarbiat Modares University, Tehran, Iran.
authors.forename: Ali Ahmadi
authors.initials: AA
authors.lastname: Peyghan
authors.affiliation: Institut de Chimie Moléculaire de Reims, CNRS-Université de Reims Champagne-Ardenne, BP 1039 51687, Reims cedex 2, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Muzart
authors.affiliation: Faculty of Modern Technologies, Chemistry & Chemical Engineering Research Center of Iran (CCERCI), Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Zadmard
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D047250:Calixarenes / Q000737:chemistry*; D002414:Cations, Monovalent / Q000032:analysis; D005456:Fluorescent Dyes / Q000737:chemistry*; D008958:Models, Molecular; D010636:Phenols / Q000737:chemistry*; D012834:Silver / Q000032:analysis*; D013050:Spectrometry, Fluorescence / Q000379:methods; D013830:Thiadiazoles / Q000737:chemistry*
chemical_list: D002414:Cations, Monovalent; D005456:Fluorescent Dyes; D010636:Phenols; D013830:Thiadiazoles; C121325:calix(4)arene; D047250:Calixarenes; D012834:Silver
keywords: Amino thiadiazole ligand; Calix[4]arene; Cation receptor; DFT studies; Fluorescent sensor; Physiological environment; Silver(I) recognition