A programmed temperature vaporizer (PTV) injection technique has been recently implemented in our laboratory. In present paper its performance is compared with other GC injection techniques commonly used in trace analysis of organic contaminants. Twenty-six pesticides representing different chemical classes were selected for the study. This group comprised compounds typically subjected to discr...

Homogeneous and mixed adlayers composed of an alkanethiol (1-octadecanethiol, ODT) and a peptide (CGISYGRKKRRQRRR) on GaAs(100) were formed in two different solvent systems: phosphate-buffered saline (PBS) and N,N-dimethylformamide (DMF). The chemical composition of each adlayer was characterized by X-ray photoelectron spectroscopy (XPS). The data showed that the makeup of the adlayer and its s...

We explore the effects of particle size and solvent environment on the thermodynamic stability of two pairs of polymorphs subjected to ball-mill neat grinding (NG) and liquid assisted grinding (LAG). Two systems were studied: (i) forms I and II of a 1 : 1 theophylline : benzamide cocrystal and (ii) forms A and B of an aromatic disulfide compound. For both systems, the most stable-bulk polymorph...

Soft lithographic techniques were used to fabricate polymeric microparticles for drug delivery applications. The microparticles were made of thermoplastics and thermosets from different types of precursors including reactive resin and polymer solutions in organic solvents or water. The microparticles produced using these methods were made of widely used polymers for drug delivery with highly un...

A new phenomenological model is developed to describe the sorption of surfactants on solids in non-aqueous media. This is based on the use of interaction parameters (delta) among solid, solute and solvent to assess the degree of the various interactions and computing an effective interaction parameter for the entire system represented by delta eff = abs{A|delta solid - delta solvent| + B|delta ...

Cholesterol gallstone disease, so common in the western world, ‘has consider&le medical and economic importance. Under normal physiological conditions, cholesterol is held in solution in the bile. If the solubility of cholesterol in bile is changed, cholesterol crystals will precipitate and lead to the formation of gallstones. The solubility of cholesterol in bile depends on three major lipid c...

Microencapsulated dosage forms represent effective new therapeutic platforms. This special issue will cover the different interests of microencapsulation as a means to control or modify the release of drug substances from drug delivery systems. To overcome the drug stability problem, since clinical efficacies have been reported to be improved by the encapsulation of pharmaceuticals, the bioavai...

The present experimental investigation was carried out in order to explore the possible thermodynamic and interactions studies of D(+) fructose with mixed solvent of aqueous alkali metal halides at different molalities and constant temperature. Experimental values of densities and ultrasonic velocities were carried out of the ternary mixture solution D(+)fructose with aqueous NaCl ,KCl , MgCl2 ...