abstract: In this paper we describe the thin layer chromatographic separation of eight of the most frequently used benzodiazepine derivates (alprazolam, bromazepam, chlorazepate potassium, chlordiazepoxide, diazepam, nitrazepam, oxazepam) and their degradation products after acid hydrolysis. Our aim was not only to develop a simple, rapid and efficient method for their separation but also the o...

periments were therefore conducted. Various methods have already been reported for thin layer chromatography of antioxidants by Seher (1), Meyer (2), Davidek and Pokorny (3) and Jonas (4). Seher utilized a two-dimension chromatography with silica gel as the adsorbent and chloroform and benzene as the solvents for development. Gallates and related compounds and NDGA remained at the starting poin...

In a project on the analysis and standardization of Ayurvedic medicines, a chemical methodology for Dasamulam Kasayam for the comparison of market samples with a laboratory sample of Dasamulam Kasayam, and recording of characteristics like colour, consistency, smell, taste acidity, density, water soluble content and ash content. Adsorption of the Kasayam on silicagel, followed by extraction wit...

This work presents a contribution to the study of process cold production by adsorption from solar energy. In this paper, we discuss comparative operation refrigerator using silica gel-water couple and zeolite-water through dynamic modeling simulation. The mathematical model representing evolution heat mass transfer at each component has been developed. It appears that temperature two adsorbent...

Metabolic carboxylic acids are extracted, with a mixture of equal volumes of t-amyl alcohol-chloroform, from an acidifiedsample of as littleas 200 tI of urine that has been adsorbed to a short column of silicagel. Total acid in the extract is measured by titrationwith tetramethylammonium hydroxide (10 mmol/liter) to a phenolphthalein end point.There is no interferencefrom protein,creatinine, cr...

A new method for the determination of ascorbic, dehydroascorbic and 2.3-diketogulonic acids in animal tissues, blood and urine is described. The material for analysis is homogenized in the presence of stannous chloride in trichloracetic acid and the extract is divided into three aliquots: in one part the ascorbic acid is converted into dehydroascorbic acid by oxidation with bromine water, in th...