a pvc membrane fe(iii) ion selective electrode has been constructed using a new macrocyclic asmembrane carrier.the electrode exhibits a good potentiometric response for fe(iii) over a wideconcentration range 1.0×10-4 to 1.0×10-1m with a slope 19.4±0.5 mv/decade a and a working phrange of 6.5-9.0. it has a fast response time ≤30s.the best performance was observed with themembrance having the 30....

A poly(vinyl chloride)-based membrane of 3,4:11,12-dibenzo-1,6,9,14-tetraazacyclohexadecane with sodium tetraphenyl borate (NaTPB) as an anion excluder and dibutylphthalate (DBP), dibutyl(butyl)phosphonate (DBBP), tris(2-ethylhexyl)phosphate (TEHP) and tributyl phosphate (TBP) as a plasticizing solvent mediator was prepared and investigated as a Cd2+-selective electrode. The best performance wa...

The complexation reactions between the macrocyclic ionophore, p-isopropylcalix[6]arene and Cs+ cation were studied in dimethylsulfoxide-acetonitrile (DMSO-AN) binary non-aqueous solvents at different temperatures using a conductometry method. The conductance data show that the stoichiometry of the (p-isopropylcalix[6]-arene·Cs)+ complex in all binary mixed solvents is 1:1. The stability of the ...

A polystyrene-based membrane of 2,10-dimethyl-4,12-diphenyl-1,5,9,13tetraazacyclohexadeca-1,4,9,12-tetraene macrocyclic ionophore was prepared and investigated as Cr(III)-selective electrode. The best performance was observed with the membrane having the polystyrene-ligand-dibutylphthalate-sodiumtetraphenyl borate composition 1:4:1:1 with a Nernstian slope of 19.0 mV per decade of concentration...

The macrocyclic ligands 3,8,12,17-tetramethyl-2,18,9,11-bipyridyl-1,4,7,10,13,16hexaazacyclooctadecanetetrahydro bromide has been synthesized and explored as suitable ionophores for chloride selective membrane sensors. It displays Nernstian behavior (59.2 mV decade-1) across the range of 4.1 × 10-8 to 1.0 × 10-2 M. The detection limit of the electrode is ~ 15 nM and the response time and life t...

Apoptosis, a mechanism of programmed cell death that removes superfluous and harmful cells, is important both during development and in tissue homeostasis. Although Zn2+ is believed to be critical in apoptosis, the precise details of its role have yet to be elucidated. The macrocyclic Zn2+ ligand dansylamidoethylcyclen [L1*(HCl)4*(H2O)2], which is found primarily in a diprotonated form (H2L1), ...

Peripheral blood cells from nine patients with B-chronic lymphocytic leukemia (B-CLL) were treated in vitro with bryostatin 1 (a macrocyclic lactone derived from a marine invertebrate). Like the phorbol ester 12-0-tetradecanoyl-phorbol 13-acetate (TPA), bryostatin 1 activates protein kinase C (PKC), which plays a central role in the phosphatidylinositol signal transduction pathway. The effects ...

The macrocyclic complexes of biological importance with power transition metals are synthesized by template methodology leading to the formation of the complex [MLX] X2; where L is macrocyclic ligand derived from 3,4-diaminotoluene, 2,4-thiazolidinedione, M=Cr (III) and Fe(III) X is Cl-, CH3COO- or NO3_.Characterisation of these complexes are through with the assistance of elemental analyses(CH...

The precise analysis of redox chemistry of MN4-based macrocyclic complexes is of great importance because of stabilization of unusual oxidation states of metal ions by macrocyclic ligand and thus have various applications in biochemistry, electrochemistry, electrocatalysis, pharmaceuticals etc. In this work, MN4-macrocyclic complexes of Co (II) and Ni(II) transition metal ...