Two new symmetrical bis-thiourea, 2,2'-[{(terephthaloylbis(azanediyl)bis(carbonothioyl) bis(azanediyl)}dipropanoic acid] (1A) and 3,3'-[{(terephthaloylbis(azanediyl)bis (carbonothioyl)bis(azanediyl)} dipropanoic acid] (1B) were synthesized by the reaction of terephthaloyl chloride with α- and β-alanine in good yields. Their binding properties were investigated with various metal cations using U...

Divalent cations are involved in the function of bacteriorhodopsin (bR) as a light-driven proton pump. If cations are removed from purple membranes they become blue. Divalent cations such as Ca2+ or Pb2+ or trivalent ions, can be stoichiometrically titrated back on to these deionized membranes. The color transitions as a function of ion concentration for Ca2+ or Pb2+ are precisely comparable an...

Flat-sheet-supported liquid membranes incorporating lasalocid A (a natural ionophore), were previously shown to be permeable to metal cations (Cd2+ and Zn2+) against a proton gradient (∆pH), which is the driving force of the process [1]. This transport process has been extended to other metal species such as Pb2+, Na+, and Ag+ and also to the case where two metal species compete for transport. ...

The aim of this study was to determine the in vitro inhibitory effects some metal ions (silver ion (Ag+), cadmium (Cd2+), cobalt (Co2+), copper (Cu2+), nickel (Ni2+), lead (Pb2+) and zinc (Zn2+)) on glutathione reductase (GR) enzyme activities that purified from gill, kidney liver tissues Capoeta umbla. For purpose, C. umbla freshwater fish using ammonium sulfate precipitation affinity column c...

Anomalous small angle scattering measurements have been applied to diluted solutions of anionic polyacrylates decorated by specifically-interacting Pb2+ cations, revealing partial collapse of the polyacrylate into pearl-like subdomains with a size on the order of a few nanometers. From the pure-resonant scattering contribution of the Pb2+ cations, and from subsequent analysis of the resonant-in...

Reaction of chromium(III) precursors with TeO2 in PbF2/PbO melts in air led to oxidation of chromium(III) to chromium(VI), whereas tellurium remained its oxidation state of IV. In the resulting title compound, Pb2(CrO4)(TeO3), the two types of anions are isolated from each other, hence a double salt is formed. The two independent Pb2+ cations exhibit coordination number nine under formation of ...

The study of binding affinity is essential in surface plasmon resonance (SPR) sensing because it allows researchers to quantify the affinity between the analyte and immobilised ligands of an SPR sensor. In this study, we demonstrate the derivation of the binding affinity constant, K, for Pb2+ and Hg2+ ions according to their SPR response using a gold/silver/gold/chitosan-graphene oxide (Au/Ag/A...

background: silica aerogel is the nano-porous form silica which is the lightest synthetic solid material. some specific properties of this material include high surface area (1500 m2.g-1), low density (< 0.03 g.cm-3) and high porosity (%99). in this research, silica aerogel was investigated as an adsorbent of the heavy metal cations in aqueous solutions. methods: the silica aerogel was synthesi...

Hydrogels containing benzo-18-crown-6 were used to modify microcantilevers for measurements of the concentration of Pb2+ in aqueous solutions. These microcantilevers undergo bending deflection upon exposure to solutions containing various Pb2+ concentrations as the result of a swelling of the hydrogels. It was found that a concentration of 10(-6) M Pb2+ can be detected using this technology. Ot...