Available surface complexation models for birnessite required the inclusion of bidentate bonds or the adsorption of cation-hydroxy complexes to account for experimentally observed H/M exchange. These models contain inconsistencies and therefore the surface complexation on birnessite was re-examined. Structural data on birnessite indicate that sorption sites are located on three oxygens around a...

Central to Alzheimer's disease (AD) is the assembly of amyloid-beta peptide (Aβ) into fibrils. A reduction in pH accompanying inflammation or subcellular compartments, may accelerate fibril formation as approaches Aβ’s isoelectric point (pI). Using global fitting kinetics over a range pHs, we identify impact net charge has on individual microscopic rate constants. We show that primary nucleatio...

1H and 13C NMR measurements were carried out to explore anticipated correlations between chemical shifts versus thiolate basicities redox potentials of cysteamine, homocysteine, penicillamine, their homodisulfides. All analyzed statistically evaluated. The closest correlation was observed for the αCH nuclei concerning data. Since neither site-specific nor can be directly measured by any means i...

Many thiol-containing molecules show heavy metal complexation ability and are used as antidotes. In this study, the potential function associated with thiol-containing peptides (TCPs) from soy protein hydrolysates as natural detoxicants for heavy metals is reported. TCPs enriched by Thiopropyl-Sepharose 6B covalent chromatography had different molecular weight distributions as well as different...

Cyclic voltammetry was used to determine the stability constants for the complexation of cadmium and zinc ions with hydroxyl-terminated polyamidoamine generation 2 dendrimers with an ethylenediamine core (PAMAM G2-OH) at a mercury ultramicroelectrode. Cadmium and zinc ions were found to form poly-metal complexes through the interactions with interior amino groups rather than hydroxyl groups and...

the determination of formation constants of binary inner transition metal complexes where m=y(iii) or la(iii) or ce(iii) or pr(iii) or nd(iii) or sm (iii) or gd (iii) or dy (iii) or th(iv) andl = creatinine have been carried out using irving–rossotti titration technique in aqueous mediaat different temperatures and at ionic strength. to understand more about the nature ofequilibrium involving i...

A series of charge ladders of bovine carbonic anhydrase II were synthesized and the relative abundances of the rungs analyzed by capillary electrophoresis as a function of the quantity of acylating agent used. A simulation that models the kinetics of formation of the members of the charge ladders is described. The observed rate constants decreased as the extent of acylation increased. These rat...

Diosmin, a vascular-protecting agent, is practically insoluble in water, and its oral absorption is limited by its extremely low dissolution rate. In this study, β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPβCD) were obtained to improve the solubility and dissolution rate of diosmin. Phase solubility studies of diosmin with βCD and HPβCD in distilled water were conducted to charac...

The complexation reactions between diacetyl monooxime (Damo), imidazole (Him), histamine (Hist) and histidine (His) with Co2+, Ni2+ and Cu2+ were studied potentiometrically in aqueous solution at 25 °C and m= 0.5 M KNO3. The overall stability constants log b's of species were obtained by computer refinement of p...

Macrocyclic ligands form highly selective and kinetically labile complexes with a wide range of cations, including alkali metal and alkaline earth cations. Formation rate constants are high and remarkably insensitive to ligand structure, but decrease systematically with increasing charge density of the cation this behaviour is qualitatively similar to that expected for the dissociative intercha...