The aim of this study was to investigate the influence of pH, buffer species and ionic strength on the release mechanism of Glipizide (G) from matrix tablets containing chitosan and xanthan gum prepared by a hot-melt extrusion process. The release mechanisms were controlled by the solubility and ionic properties of the polymers. All directly compressed (DC) tablets prepared in this study also e...

Applying isotachophoresis (ITE’) superimposed on capillary zone electrophoresis (CZE), which will be denoted the ITPlCZE mode, components migrate in an ITP way on top of a background electrolyte. In such an ITPKZE system the leading electrolyte consists of a mixture of an ionic species L, with a high mobility (the leading ion of the ITP system), an ionic species L, with low mobility (the co-ion...

Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim(+)][Tf(2)N(-)]), and a reactive hypergolic ionic liquid, 1-Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim(+)][Dca(-)]), are generated by vaporizing ionic liquid submicrometer aerosol particles for the first time; the vaporized species are investigated by dissociative ionizatio...

Deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase (EC 2.7.7.6) from Acinetobacter calcoaceticus was purified to apparent homogeneity and its properties were compared with those of the Escherichia coli B enzyme. The molecular weights of the two native active enzymes as well as their alpha and beta subunits appeared to be similar. No subunit corresponding to that of sigma fr...

We quantitatively modeled the volume phase transition of a hydrogel containing a crystalline colloidal array with a crown ether ligand which binds Pb2+. The hydrogel volume response and the wavelength diffracted depend on the Pb2+ concentration and on both the ionic strength and the valence of the nonbinding ionic species. We successfully modeled the response of this hydrogel Pb2+ sensor to ion...

inherent differences observed in ionic composition of gastrointestinal contents due to diet, feeding regimen and (or) site along the length of the digestive tract were controlled so that a clearer understanding of species differences could be obtained. Three species of ruminants (i.e., Zebu cattle, sheep and goat), a pseudo-ruminant (camel) and a nonruminant (donkey) were compared. Specific dif...

New polyethylene glycol (PEG)/ionic liquid aqueous biphasic systems (ABS) are presented. Distinct pairs of PEG polymers and ionic liquids can induce phase separation in aqueous media when dissolved at appropriate concentrations. Phase diagrams have been determined for a large array of systems at 298, 308 and 323 K. A comparison of the binodal curves allowed the analysis of the tunable structura...