Gas chromatographic-mass spectrometric analysis of urinary glycyrrhetinic acid: an aid in diagnosing liquorice abuse

Gas-chromatographic Mass-spectrometric Detection

Cystathionine has been reported to undergo enzymatic changes leading to the formation of seven membered cyclic products (Ricci, G., Santoro, L., Achilli, M., Matarese, R. M., Nardini, M., and Cavallini, D. (1983) J. Biol. Chem. 258, 10511-10517; Cavallini, D., Costa, M., Pensa, B., and Coccia, R. (1985) Biochem. Int. 10, 641-646). Gas-chromatographic and mass-spectrometric evidence reported in...

Alternative Sample Preparation Techniques in Gas Chromatographic - Mass Spectrometric Analysis of Urinary Androgenic Steroids

Gas chromatographic and mass spectrometric analysis of nitrilotriacetic acid in environmental aqueous samples.

This study describes a fast and accurate method for the sample preparation, identification, and quantitation of nitrilotriacetic (NTA) acid in environmental aqueous samples at a concentration of ppb level. The method is sensitive, specific, and free from the interferences of fatty and amino acids. The tri-n-propyl- and tri-n-butyl-NTA acid esters were prepared by the reaction of n-propyl-HCl an...

Gas-chromatographic/mass-spectrometric determination of theophylline in whole blood.

We describe a combined gas-chromatographic mass-spectrometric method for determination of theophylline in whole blood. With use of a probability-based matching approach, the extensive gas-chromatographic interference did not affect mass-spectrometric quantitation of theophylline. Concentrations expected and found were linearly related from 1 to 60 mg/liter; the run-to-run coefficient of variati...

Gas-chromatographic-mass-spectrometric determination of urinary acid profiles of normal young adults on a controlled diet.

Studies aimed at the determination of normal values of various endogenous urinary metabolites have been of two types-analytical techniques designed to quantitate some individual component or methods developed to study members of a related class of compounds. While quantitation of individual components is useful in the diagnosis of many disease states, it is advantageous to study a wide range of...