Select The Theory Behind Gas Chromatography

Gas chromatography is an older Analytical technique that is still widely used today. It is a technique which can be used with both organic and inorganic analytes, but the one requirement is that the sample has to be volatile, otherwise the analysis will not work. The technique has witnessed a great deal of use across several industries and it is often coupled with other methods, most commonly mass spectrometry. Here, we are going to examine how gas chromatography works. Gas chromatography is often used to determine the purity of an Unknown substance or to separate out the components of an unknown mixture so that each of the various parts can be examined. It is a technique which can be used to detect samples in very tiny quantities.

Gas Chromatography

In general, these tools have an inlet area, where the carrier gas and sample are injected into the device, a chromatographic column that is heated to make sure that all of the elements are gases, and a sensor area which could vary based on the requirements of the analysis. Like any chromatography instrument, the inner workings Include a mobile phase and a stationary phase. It does differ from a number of other chromatography techniques–such as liquid chromatography, high-performance liquid chromatography and thin layer chromatography –that have liquid mobile stages, as the mobile phase in gas chromatography is an inert gas. The carrier gases used are generally helium, argon or nitrogen. The stationary phase can be made up of a number of substances, but it Is commonly a polymer or another inert material i.e., one which isn’t going react to any of the gaseous molecules being examined, because any reactions cause the stationary phase to degrade.

While the stationary phase is an extremely packed solid, it is often coated with a liquid stationary phase which has a high boiling point. The general working principles are as follows gas chromatography. The sample is Injected into the tool where it is vaporized and blends with the carrier gas to be a component of the mobile stage. This mobile phase is then carried through the chromatographic column where it interacts with the static phase of the column. The connections between the stationary phase and the analyte determine the elution time of the various molecules in the sample, since if the sample interacts with the static phase longer, then it will take longer to reach the sensor. In Addition, the stationary phase has molecular pores that Different size molecules can undergo; therefore, if the molecule is smaller, then it will get a faster elution time compared to larger molecules.

Share