The kinetics of the potassium thiocyanate transport mediated by dicyclohexyl-18-crown-6 (L) through a bulk liquid membrane is studied experimentally and theoretically. The proposed model is based on the assumption of a pure diffusion of the complex salt [K·L]+SCN¯ through the liquid membrane stagnant films at the interfaces. It illustrates the ...

The objective of this work was to design and characterize liquid and solid self-emulsifying drug delivery systems (SEDDS) for poorly soluble atorvastatin. To optimize the composition of liquid atorvastatin-SEDDS, solubility tests, pseudoternary phase diagrams, emulsification studies and other in vitro examinations (thermodynamic stability, droplet size and zeta potential analysis) were performe...

A number of polyacrylamide gel systems and solubilization procedures were studied to define the number and nature of "major" polypeptide bands in the outer membrane of Pseudomonas aeruginosa. It was shown that five of the eight major outer membrane proteins were "heat modifiable" in that their mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was determined by the solubiliza...

crown ethers 12-crown-4 (12c4), benzo-15-crown-5 (b15c5), 18-crown-6 (18c6), nitrobenzo-18-crown-6 (nb18c6) dibenzo-18-crown-6 (db18c6) and dicyclohexyl-18-crown-6 (dc18c6), dissolved in dichloromethane, are able to form oxonium-ion complexes in contact with aqueous sulfuric and hydrochloric acid solutions. this ability allows the transfer of cr(vi) oxanions from the acid media, through an orga...

The plasma membrane proteins are critical components in cellular control and differentiation and thus are of special interest to those studying signal transduction mechanisms in all organisms. When conducting proteomic studies on membrane components of cells and tissues, the complexity is not simply confined to the large number of proteins present in the sample but also to the highly hydrophobi...

A procedure for solubilization of the oxygen-labile, membrane-bound diol dehydratase from Clostridium glycolicum with retention of enzymatic activity is described. The procedure involves sonication of crude membrane preparations anaerobically in 0.1 M 2-(N-cyclohexylamino)ethane-sulfonic acid (CHES) buffer (pH 8.6-9.0) containing 2 mM dithiothreitol. The addition of dimethylsulfoxide (30%) and ...

The minimum surface tension and respreadability of a surfactant monolayer is limited by a two to three dimensional instability called collapse. Liquid-condensed or solid phase monolayers collapse via fracture followed by loss of material. Liquid-expanded phase monolayers collapse by solubilization into the subphase. Monolayers that retain a continuous liquid-expanded phase network surrounding i...