Title
Multivalent Calix[4]arene-Based FluorescentSensorfor Detecting Silver Ions in Aqueous Media and Physiological Environment
Author
Behzad Lotfi, Aliakbar Tarlani, Peyman Akbari-Moghaddam, Maryam Mirza-Aghayan, Ali Ahmadi Peyghan, Jacques Muzart, Reza Zadmard
Year
2016
Journal
Biosensors and Bioelectronics
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 Rand 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 forcomputational 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 scaffoldandmolecular 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 cationswasexamined and showed gradual emission enhancement which makes R an ideal candidate for monitoring of Ag+ in physiological environment.
Instrument
FP-6500
Keywords
Fluorescence, Coordination chemistry, Sensors, Materials