Gas Chromatography Lab Report

INTRODUCTION
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.

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 can be used 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

If a better resolution is desired, reduce the velocity to not less than 50 cm/sec; however, the analysis time will be increased. If a shorter analysis time is desired, increase the velocity to 70-80 cm/sec; be aware of potential resolution losses at these higher linear velocities. Average linear velocities of 60-70 cm/sec are used for many analyses when using hydrogen as carrier gas. The choice of gas to be used as mobile phase in gas chromatography is influenced by the following requirements and considerations: Inertness, Dryness, Freedom from oxygen, Safety, Cost, and