Gas chromatographic determination of some carboxylic acids: comparison between solution and headspace analysis

Abstract

Direct and headspace gas chromatographic analysis is compared for the determination of lactic, oxalic, succinic, malic and citric acids. For better chromatographic behaviour, prior to GC analysis carboxylic acids were derivatized using BSTFA as a silylation reagent. Three solvents – acetone, diethyl ether and dimethylformamide – were tested as a derivatization medium and DMF was considered as the best. Derivatization conditions were optimized and analytical characteristics of the direct gas chromatographic determination of analytes in solutions were determined. The method was applied for the determination of citric acid in food. For the analytes dissolved in DMF, the headspace gas chromatographic determination was not sensitive enough. Concentrations of the derivates in the headspace were very low, thus the limits of detection were high and the method was not of practical use. On the other hand, headspace gas chromatography can be applied for identifying of carboxylic acids in solid samples.

WITHDRAWN: Microscopic Reaction Mechanism of Formic Acid Generated During Pyrolysis of Cellulosic Insulating Paper

“…Meanwhile it shows the reliability of the BSTFA silanization derivatization method in detecting formic acid molecules. The silylation reaction between the silylation reagent BSTFA and formic acid is that the methylsilyl group in BSTFA replaces the carboxyl hydrogen in formic acid, which generates formic acid TMS derivative (Bugelytė et al 2019). The reaction formula is shown in This paper analyzed the pyrolysis of cellulose molecules to generate formic acid molecules at 1600K-2600K.…”

Gas chromatography for β-caryophyllene determination in St. John’s wort infused oil

“…However, the preparation of multicomponent plant samples for gas chromatographic analysis is often complex and time-consuming. A perfect choice for the determination of volatile compounds is GC combined with headspace sampling [17,18]. One of the most convenient mathods that combines GC and headspace sampling is static headspace gas chromatography (SHS-GC).…”