Open tubular gas chromatography

Application of the Design Equations to Packed Liquid Chromatography Columns and Open Tubular Gas Chromatography Columns... 

Table 23-3 compares the performances of packed and open tubular gas chromatography columns with the same stationary phase. For similar analysis times, the open tubular column gives resolution seven times better (10.6 versus 1.5) than that of the packed... 

Figure 24-2 (d) Typical dimensions of open tubular gas chromatography column. 

Theoretical performance in gas chromatography. As the inside radius of an open tubular gas chromatography column is decreased, the maximum possible column efficiency increases and sample capacity decreases. For a thin stationary phase that equilibrates rapidly with analyte, the minimum theoretical plate height is given by... 

Consider the open tubular gas chromatography of n-Cl2H26 on a 25-m-long X 0.53-mm-diameter column of 5% phenyl-95%... 

J. V. Hinshaw and L. S. Ettre, Introduction to Open Tubular Gas Chromatography (Cleveland, OH Advanstar Communications, 1994) H. M. McNair and J. M. Miller, Basic Gas Chromatography (New York Wiley, 1998) R. L. Grob and E. F. Barry, eds.. Modern Practice cfGas Chromatography (New York Wiley, 2004). 

S. T. Adam, Quality test of a mechanical switching valve for two-dimensional open tubular gas chromatography , J. High Resolut. Chromatogr. Chromatogr. Commun. 11 85-89(1988). 

Bao, J., N. Nazem, L.T. Taylor, J. Cynko, and K. Kyle. 2006. Negative temperature programming using microwave open tubular gas chromatography. J. Chromatogr. Sci. 44 108-112. 

J. Hinshaw, Programmed temperature injection in open tubular gas chromatography, Instrum. Res., 14-24 (1985). 

Pyrolysis studies of oil shale, gas phase subtractive investigations of evolved volatiles, and open tubular gas chromatography— vapor-phase IR spectroscopy of shale oil components were carried out in the interfaced vapor-phase thermal analysis laboratory which has been described in detail elsewhere (4,5). A general block diagram of this system is shown in Figure 1. 

The basic fish oil (27) also included a generous amount of saturated fatty acids. As can be seen from Figure 5 and Table 1, the saturated fatty acids are dominated by the 16 0 (palmitic acid), usually accompanied by about half as much or less of 14 0 (myristic acid) and much less of 18 0 (stearic acid). Usually the saturated fatty acid totals are at least 20%, especially as the odd chain (15 0, 17 0) and methyl-branched (iso, anteiso, pristanic, phytanic) fatty acids (compare Figure 4) are sam-rated and will total around 2-3%. An unsaturated peak that is often observed is 17 ln-8, which is roughly equal to 17 0. The details of these peaks are discussed in other publications, but those researchers attempting modern open-tubular gas chromatography analyses should be aware of their presence and influence on peak identification and quantitation. As can be seen from Figure 6, there is an... 

Gross, G.M., Grate, J.W. and Synovec, R.E. (2004) Monolayer-protected gold nanoparticles as an efficient stationary phase for open tubular gas chromatography using a square capillary Model for chip-based gas chromatography in square cornered microfabricated channels. J Chrom A, 1029 (1-2), 185-192. 

Many early results for erucic acid actually included total C22 fatty acids since the analysis was performed on nonpolar columns in order to save time and increase sample throughput. Present day analyses are usually carried out using polar phases, including a mixed phase which allows separation of all major fatty acids according to chain length and degree of unsaturation. Erucic acid values reported from these analyses still contain very small amounts of vaccenic and brassidic acids. It is necessary to use open tubular gas chromatography to determine these isomers. 

Gross GM et al (2003) Monolayer-protected gold nanoparticles as a stationary phase for open tubular gas chromatography. Anal Chem 75(17) 4558-4564... 

Figure 22-4 Resolution of 22 18-carbon fatty acid methyl esters with 1, 2, or 3 double bonds. Fatty acids shown in Figure 5-3 are labeled (peaks 3, 7, and 14). A Supelco ILIOO ionic liquid wall-coated open tubular gas chromatography column (100 m X 0.25 mm inner diameter with 0.20 xrr film thickness) was operated at 150°C with H2 carrier gas at a linear flow rate of 25 cm/s and flame ionization detection. [From C. Ragonese, P. Q. Tranchida, P. Dugo,...

Consider a narrow-bore (0.25 mm diameter) open tubular gas chromatography column coated with a thin film (0.10 xm thick) of stationary phase that provides 5 000 plates per meter. Consider also a wide-bore (0.53 jim diameter) column with a thick film (5.0 xm thick) of stationary phase that provides 1 500 plates per meter. 

The initial theoretical work on open-tubular gas chromatography (Golay) and on packed-column liquid chromatography (van Deemter) was published as early as the 1950s. These papers led to the development of commercial gas chromatographs using capillaries with micrometer diameters, and liquid chromatographs with micrometer-scale particles for the stationary phase. 

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