Gas Chromatograph: The Principles Of Gas Chromatography

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A gas chromatograph (GC) can be utilized to analyze the contents of a sample quantitatively or in certain circumstances also qualitatively. In the case of preparative chromatography, a pure compound can be extracted from a mixture. The principle of gas chromatography can be explained as following: A micro syringe is used to inject a known volume of vaporous or liquid analyte into the head or entrance of a column whereby a stream of an inert gas acts a carrier (mobile phase). The column acts as a separator of individual or chemically similar components. A column is typically packed with a stationary non-volatile matter (stationary phase). The separation occurs due to different interactions of each component with the stationary phase. The factors …show more content…

Typical applications pertain to the quantitative and/or qualitative analysis of food composition, natural products, food additives, flavor and aroma components, a variety of transformation products, and contaminants, such as pesticides, fumigants, environmental pollutants, natural toxins, veterinary drugs, and packaging materials. And particular food applications involving GC, such as carbohydrates and amino acids. Lipids and accompanying lipophilic compounds. flavors and aroma. GC could be of use for the direct separation and analysis of gaseous samples, liquid solutions, and volatile solids. If the sample to be analyzed is non-volatile, the techniques of derivatization or pyrolysis GC can be utilized. Gas chromatography (GC) has been an indispensable analytical technique in the application of fatty acid determinations in oilseed plant breeding, biosynthesis, and human metabolism. As well as the characterization of complex mixtures of geometric isomers when combined with other chromatographic separations and spectroscopic identification. Plant cultivators utilize GC as a more accurate and fast method to evaluate the differences and inheritance of fatty acids in oilseed crops such as rapeseed. flaxseed, and safflower.
Optimum qualitative and quantitative GC analysis of complex mixtures requires:
• good resolution, as shown by distinctive and symmetric …show more content…

Since the molecules that to be analyzed should be thermally stable and sufficiently volatile, the application area of the gas chromatograph is limited. The number of molecules does not meet these requirements and hence are not responsive to direct gas chromatograph analysis.
REFERENCES
1. Grob, Robert L., and Eugene F. Barry, eds. Modern practice of gas chromatography. John Wiley & Sons, 2004.
2. I.A. Fowlis, Gas Chromatography-Analytical chemistry by open learning, 2nd Ed., John Wiley & Sons, 1995.
3. Kaal, Erwin, and Hans-Gerd Janssen. "Extending the molecular application range of gas chromatography." Journal of Chromatography A 1184. 1 2008, pp. 43-60.
4. Marriott, Philip J., Robert Shellie, and Charles Cornwell. "Gas chromatographic technologies for the analysis of essential oils." Journal of Chromatography A 936.1, 2001, pp. 1-22.
5. Molnár-Perl, I. "Role of chromatography in the analysis of sugars, carboxylic acids and amino acids in food." Journal of Chromatography A 891.1 2000, pp.

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