A new extension of the Hildebrand solubility approach which describes drug solubility in solvent mixtures showing multiple solubility peaks, the chameleonic effect, is proposed. The experimental solubilities of oxolinic acid were measured at 25 degrees C in solvent mixtures of ethanol-water and ethanol-ethyl acetate. A plot of the mole fraction of the drug against the solubility parameter (delt...

Zwitterionic co-crystals family could be basis for very different structural and theoretical examinations as their ability to alter solubility and deliver a wide solubility spectrum is receiving more attention. Many zwitterionic co-crystals crystal structures exhibited carboxylate-hydroxyl supramolecular heterosynthons preference. In addition to examples of zwitterionic co-crystals in the Cambr...

Development of colonic diverticulosis is a function of age and declining colonic wall mechanical strength. The latter is partly a consequence of changes in the collagen structure. Collagen from unaffected human colons (n = 20, age range 20-80 years) and those with colonic diverticulosis (n = 5, age range 67-80 years) were obtained at necropsy. The total collagen content was measured as the hydr...

One of the greatest bottlenecks in producing recombinant proteins in Escherichia coli is that over-expressed target proteins are mostly present in an insoluble form without any biological activity. DCase (N-carbamoyl-D-amino acid amidohydrolase) is an important enzyme involved in semi-synthesis of beta-lactam antibiotics in industry. In the present study, in order to determine the amino acid si...

The main objective of this study was to develop an effective potentiometric saturation titration protocol for determining the aqueous intrinsic solubility and the solubility-pH profile of ionizable molecules, with the specific aim of overcoming incomplete dissolution conditions, while attempting to shorten the data collection time. A modern theory of dissolution kinetics (an extension of the No...

Greenhouse gas CO2 emissions to the atmosphere are believed to be the primary reason for the global warming. One effective way to mitigate CO2 emissions is to capture CO2 from post-combustion flue gas in coal-fired power plants. Membrane technology has been widely explored for this application due to its high energy-efficiency. Current membrane materials are often based on poly(ethylene oxide) ...

background valproic acid is widely used as an anticonvulsant and mood-stabilizing drug in the treatment of epilepsy. determination of serum valproic acid is required in epilepsy therapy for efficient control of seizures. objectives in the present study, the gas chromatography method was applied to determine serum valproic acid and resulting data were compared with those obtained by high perform...

Measurements of the rate of uptake of soluble gases such as nitrous oxide or acetylene has been used as the basis of a method of cardiac output estimation since 1912. Using theoretical models of single, multiple and rebreathing techniques of cardiac output measurement, we determined the effect of solubility in blood and lung tissue on the changes in the final expired concentration of the gas. D...