Direct determination of dissolved oxygen in soil water by gas chromatography

Abstract A method is described for the determination of pentachlorophenol (PCP) in gelatin. The method employs acid and heat to hydrolyze the gelatin matrix, a base partition and wash for separation and cleanup, and a reacidification and extraction with hexane for direct determination of PCP, without preparation of a derivative, using gas chromatography (GC) with a 1% SP-1240DA liquid phase and a 63Ni electron capture detector. Recoveries averaged 106% for fortifications between 0.02 and 1.0 ppm. The limit of quantitation is 20 ppb. The limit of detection is 4-6 ppb. The method, which has undergone a successful intralaboratory trial, is simple and rapid, and requires only general laboratory reagents and equipment. GC of the acetate derivative of PCP is used for confirmation of identity.

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Direct determination of chlorophenols in landfill leachates by solid-phase micro-extraction–gas chromatography–mass spectrometry

Journal of Chromatography A ◽

10.1016/s0021-9673(02)01280-3 ◽

2002 ◽

Vol 975 (2) ◽

pp. 267-274 ◽

Cited By ~ 116

Author(s):

A Ribeiro ◽

M.H Neves ◽

M.F Almeida ◽

A Alves ◽

L Santos

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Solid Phase ◽

Direct Determination ◽

Gas Chromatography Mass Spectrometry ◽

Solid Phase Micro Extraction ◽

Landfill Leachates ◽

Chromatography Mass Spectrometry

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Direct determination of poly(3-hydroxybutyrate) accumulated in bacteria by thermally assisted hydrolysis and methylation-gas chromatography in the presence of organic alkali

Pure and Applied Chemistry ◽

10.1515/pac-2017-0905 ◽

2018 ◽

Vol 90 (6) ◽

pp. 1011-1017 ◽

Cited By ~ 2

Author(s):

Siti Baidurah ◽

Yasuko Kubo ◽

Yasuyuki Ishida ◽

Tsuneo Yamane

Keyword(s):

Gas Chromatography ◽

Solvent Extraction ◽

Carbon Source ◽

Sole Carbon Source ◽

Agar Medium ◽

Direct Determination ◽

Sample Pretreatment ◽

Bacterial Cells ◽

Gravimetric Determination

Abstract There is considerable interest in the development of simple methods for quantifying production of the biodegradable polyester poly(3-hydroxybutyrate) [P(3HB)] by bacteria. Cells of Cupriavidus necator were grown on agar medium containing different concentrations of glucose (10–25 g/L) as a sole carbon source. Trace amounts (100±5 μg) of dried C. necator cells were directly subjected to thermally assisted hydrolysis and methylation-gas chromatography (THM-GC) in the presence of tetramethylammonium hydroxide (TMAH). On the resulting chromatograms, a series of characteristic peaks, attributed to the THM products from poly(3-hydroxybutylate) accumulated in the bacterial cells, were clearly observed without any interfering component. Based on the peak intensities, the contents of P(3HB) in C. necator were determined precisely and rapidly without using any cumbersome sample pretreatment. Furthermore, the values of the P(3HB) contents coincided overall with those obtained by the conventional method involving solvent extraction followed by gravimetric determination.

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