Determination of Dichlorohydrin in Process Streams by Gas-liquid chromatography using mixed stationary phases

Capillary gas-liquid chromatography with three columns impregnated with non-polar, medium and polar stationary phases has been used for determination of the Kováts indexes of methylethyl- and trimethylbiphenyls carrying the alkyl groups in the both rings. From elution data of isomeric methyl- and ethylbiphenyls the increments of methyl and ethyl groups have been determined, the theoretical Kováts indexes of the mentioned methylethyl- and trimethylbiphenyls have been calculated, and possibility of prediction and assessment of the Kováts indexes of these substances has been discussed. Parameters of the straight line given by the relation IApiez.L = k . Istat.phase(2) + q have been determined, and correlation coefficients of these relations have been estimated.

Download Full-text

Amino acid composition of human nail, as measured by gas-liquid chromatography.

Clinical Chemistry ◽

10.1093/clinchem/22.10.1608 ◽

1976 ◽

Vol 22 (10) ◽

pp. 1608-1613 ◽

Cited By ~ 14

Author(s):

M Greaves ◽

J M Moll

Keyword(s):

Amino Acid ◽

Stationary Phases ◽

Methyl Esters ◽

Gas Liquid Chromatography ◽

Acid Methyl ◽

Mixed Stationary Phases ◽

Amino Acid Analyzer ◽

Liquid Chromatographic Analysis ◽

Liquid Chromatographic

Abstract We describe a quantitative method for determination of histidine and 16 other amino acids in a nail hydrolysate. This is based on the formation of trifluoroacetyl amino acid methyl esters and gas-liquid chromatographic analysis with use of two columns of mixed stationary phases. Histidine is determined as a triple derivative Nalpha-trifluroacetyl-Nim-carbethoxy methyl histidinate. The specificity and reproducibility of the method are illustrated. As little as 1 mg of amino acid per gram of nail can be determined, and 15 hydrolysates can be completely analyzed in 10 working days. Data obtained from multiple analyses of 10 nail hydrolysates by the method described closely parallel those obtained in another laboratory, in which an amino acid analyzer was used.

Download Full-text

GASCHROMATOGRAPHIC DETERMINATION OF STEROIDS IN THE URINE OF PATIENTS WITH CUSHING'S SYNDROME

Acta Endocrinologica ◽

10.1530/acta.0.0670303 ◽

1971 ◽

Vol 67 (2) ◽

pp. 303-315 ◽

Cited By ~ 14

Author(s):

A. J. Moolenaar ◽

A. P. van Seters

Keyword(s):

Liquid Chromatography ◽

Cushing’S Syndrome ◽

Normal Subjects ◽

Diagnostic Value ◽

Cushing's Syndrome ◽

Gas Liquid Chromatography ◽

Obese Subjects

ABSTRACT The 17-oxosteroids were estimated in the urine of 27 patients with Cushing's syndrome by gas-liquid chromatography (G. L. C.). The values of the various steroid fractions are compared with those of normal subjects, patients with thyrotoxicosis and obese subjects. The effect of the age of the patients on the diagnostic value of the invidual 17-oxosteroids and their ratios is discussed.

Download Full-text