Direct resistively heated column gas chromatography (Ultrafast module-GC) for high-speed analysis of essential oils of differing complexities

Abstract

This study applies Ultrafast module-GC (UFM-GC) with direct resistively heated columns to routine analysis of a group of essential oils of differing complexities (chamomile, peppermint, rosemary and sage). Essential oils were analysed by conventional GC with conventional inner diameter (i.d.) columns (0.25 mm) of different lengths (5 and 25 m long) and by Fast GC and Ultrafast module-GC with narrow bore columns (0.1 mm i.d., 5 m long). Column performance were evaluated and compared through their Grob test, separation number and peak capacity. Ultrafast module-GC was successful in the qualitative and quantitative analysis of essential oils of different compositions with analysis times between 40 s and 2 min versus 20-60 min required by conventional GC. Critical pairs or groups of components were separated by carefully tuning selectivity of the stationary phase to compensate for loss of efficiency due to the use of short columns and high temperature rates. The Ultrafast module-GC results of peppermint e.o. analyses were also validated and compared to those obtained by conventional GC; by measuring precision over time (i.e. repeatability and intermediate precision) and accuracy. Ultrafast module-GC showed a good separation reproducibility affording reliable component identification through the relative retention times and quantitative determination through normalised peak areas. Accuracy data also showed that Ultrafast module-GC and conventional GC normalised areas and areas percentage were perfectly comparable.

Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae)

“…The efficiency of the fast GC technique with a direct resistively heated column (ultra fast module-GC) was demonstrated for the analyses of various types of samples: essential oils, pesticides, lipids, etc. [20][21][22].…”

The comparative chemical study of the fatty acid composition of hawthorn flowers of Sanguineae Sarg. section

“…The study was carried out by the chromato-massspectrometry method on an Agilent Technologies 6890 chromatograph with the mass-spectrometry detector 5973 [6,7]. The chromatography parameters: introduction of the sample (2 µl) in the chromatographic column was performed in the splitless mode.…”

Rapid analysis of food products by means of high speed gas chromatography

“…Bicchi et al [30] applied ultrafast GC to the analysis of a series of essential oils by using resistively heated narrowbore columns. With respect to conventional GC applications, resolution was intentionally decreased but was maintained at a sufficient level for the separation of target compounds.…”

“…The latter reports essential information relative to each application, which will not be repeated in this section (more details may be derived by directly consulting the reference). In the field of narrow-bore column fast GC research, a total of 18 essential oil applications are reported [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43]; Table 1 also reports the use of a short conventional column in fast GC essential oil analysis [9], while eight are focussed on fatty acid methyl ester (FAME) analysis [44][45][46][47][48][49][50][51]; single works regard triglycerides [52] and an alcoholic beverage [53]. More detailed information will be provided hereafter for some of the most representative high-speed GC examples.…”