Two-dimensional gas chromatography with electron capture detection for the sensitive determination of specific mycobacterial lipid constituents

Abstract

A method was developed for determining two characteristic mycobacterial lipid constituents, tuberculostearic acid (as its pentafluorobenzyl ester) and 2-eicosanol (as its pentafluorobenzoyl ester), by using gas chromatography with electron capture detection. A microprocessor-controlled column-switching system (two-dimensional gas chromatography) facilitated sample preparation and increased specificity. The usefulness of the technique was illustrated by its ability to reveal picogram amounts of tuberculostearate in a suspension of Mycobacterium leprae isolated from a naturally infected armadillo. Two-dimensional gas chromatography with electron capture detection may in some instances provide a convenient alternative to gas chromatographymass spectrometry for use in demonstrating the presence of mycobacteria in a complex environment.

Gas chromatographic determination of D-arabinitol/L-arabinitol ratios in urine: a potential method for diagnosis of disseminated candidiasis

“…When using the latter technique, the sample is first separated on a precolumn, and a selected fraction is thereafter transferred to a cold trap which is then heated to introduce the fraction into the analytical column; thus, an efficient on-line sample purification is achieved. We have previously applied multidimensional GC to detect specific hydroxylated and branched-chain bacterial fatty acids in clinical samples (6,14), but in comparison, the GC method used in the present study is more straightforward and far better suited for routine application since standard GC instrumentation is sufficient. The The mean ± SD (range) D/L-arabinitol ratio in the 37 adult control patients was 1.8 ± 0.4 (1.0 to 2.9).…”

Applications of cellular fatty acid analysis.

“…Thus, any of the CFAs uniquely found among prokaryotes could serve as a marker of infection. In CSF, for example, TBSA has been studied most extensively in this regard (20,50,51,84,117). Such markers are useful for diagnosis when detected in normally sterile sites and in the setting of a clinical picture consistent with the agent represented by the CFA marker.…”

Use of two-dimensional gas chromatography with electron-capture detection for the measurement of lipopolysaccharides in peritoneal fluid and plasma from rats with induced peritonitis

“…not that of chenodeoxycholic acid, increases the With two-dimensional GC, only preselected fractions of tions of cell wall-dissociated LPS. The induction the total sample are introduced into the analytical column plus bile peritonitis by means of deoxycholic acid attached to the ECD (9,28). This improved selectivity, found to give a higher mortality in rats, compared although not comparable with that of GC-MS ( Fig.…”