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What is gas liquid chromatography?

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Gas liquid chromatography involves the vaporization and injection of a sample onto the top of the chromatographer's column. After that, the sample goes through the column as a result of the flow of mobile gases, while the column itself has a stationary liquid phase that adsorbs onto an inert solid surface. At this point, several different detectors can be used, yielding different sorts of selectivity.

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It is important for the carrier gas to be inert chemically, and gases that are frequently used include helium, nitrogen, carbon dioxide and argon; the specific choice generally depends on the type of detector in use.

The sample should enter the column as a vapor "plug," as a slower injection of larger samples weakens resolution and broadens the band. Most commonly, a microsyringe injects sample into a vaporizer port through a rubber septum at the column head.

To create precise outcomes, it is important to control temperatures within the column within tenths of a degree, but the optimal temperature varies with the sample's boiling point. A temperature just above the average excess of the sample yields elution time ranging between two or three minutes to half an hour. Samples that have a wide boiling range tend to respond well to temperature programming.

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