a simple and sensitive method is described for the pre-concentration by cloud point extraction followed by atomic absorption spectrometric determination of copper ion in real samples. at a solution ph of 5.5, 5, 5-diphenylimidazolidine-2, 4-dione (phenytoin) (dfid) and tritonx-114 were used as hydrophobic ligand and non-ionic surfactant. the adopted concentrations for dfid, triton x-114 and hno...

In the present study a cloud-point extraction process using non-ionic surfactant Triton X-114 for selective extraction of gallium from aqueous solutions was developed. The method is based on the complex formation of Ga (III) with N, N′ -bis (salycilidene)-1, 2-phenylenediamine (salophen) as a chelating agent in buffer media of pH 5. After phase separation and dilution of the surfactant-rich pha...

Penicillin-binding proteins (PBPs) of Treponema pallidum subsp. pallidum (T. pallidum) were characterized by using [3H]penicillin G and a conjugate consisting of ampicillin and 125I-labeled Bolton-Hunter reagent. Both antibiotics specifically radiolabeled proteins with molecular masses of 94, 80, 63, and 58 kilodaltons (kDa); 125I-labeled Bolton-Hunter reagent-ampicillin also radiolabeled sever...

Previous work has indicated that two types (A and B) of binding sites for hexokinase exist, but in different proportions, on brain mitochondria from various species. Hexokinase is readily solubilized from Type A sites by glucose 6-phosphate (Glc-6-P), while hexokinase bound to Type B sites remains bound even in the presence of Glc-6-P. Type A:Type B ratios are approximately 90:10, 60:40, 40:60,...