Chromatography – Fidar Shimi Jam

Gas Chromatography (GC)

admin — Fri, 16 Apr 2021 21:35:56 +0000

Gas chromatography is a separation technique for the analysis of volatile compounds without their breakdown. The system works on two phases, a stationary phase and a mobile phase. The mobile phase is an inert gas (commonly hydrogen, helium, nitrogen, argon, or carbon dioxide), sometimes called the carrier gas. The stationary phase is either an adsorbent solid or a thin film of a non-volatile liquid. Separation takes place when the sample tries to distribute itself between these two phases. What makes GC different than other types of chromatography is that the mobile phase does not interact chemically with the analytes.

Common types of GC inlets include split/splitless (SSL), purged packed (PP), multimode (MMI), cool-on-column (COC), and programmed-temperature vaporizing (PTV) inlets. A whole host of detectors are available to use with GC instruments, including FID, TCD, NPD, NCD, FPD+, ECD, SCD, and MSD, to name but a few, and the choice is solely down to the analytical need.

Agilent 7890B

Gas Chromatography–Mass Spectrometry (GC-MS)

admin — Wed, 10 Mar 2021 22:40:47 +0000

GC-MS is a combination of gas chromatography and mass spectrometry in which the separation ability of gas chromatography is used along with the identification power of mass spectrometry. It is one of the most popular analytical methods for samples consisting of volatile or semi-volatile compounds (liquid, gaseous, or solid). GC-MS systems are useful for determining the identity and the amount of components in a mixture of unknown composition.
GC-MS can only analyze those samples that can be injected into the GC. Typically, these are volatile substances (essential oils from plants with low boiling points) or substances that can be converted into volatile substances by derivatization. In the system, the mixture components are first separated in a GC column. After the carrier gas has been removed, the analytes are drawn into the ionization source of the mass spectrometer, where high-energy electric fields fragment and identify them based on their mass-to-charge ratios.
A major plus point for this method is its speed: components can be identified in less than 90 seconds after entering the system. GC-MS is also extraordinarily sensitive – down to the picogram range – so it is possible to determine the exact composition of complex samples with extraordinary accuracy.

GC and HPLC syringes

admin — Mon, 08 Mar 2021 08:54:06 +0000

High-Performance Liquid Chromatography–Mass Spectrometry (LC-MS)

admin — Sun, 04 Oct 2020 21:42:31 +0000

GC-MS can only analyze those samples that can be injected into the GC. Typically, these are volatile substances (essential oils from plants with low boiling points) or substances that can be converted into volatile substances by derivatization. In the system, the mixture components are first separated in a GC column. After the carrier gas has been removed, the analytes are drawn into the ionization source of the mass spectrometer, where high-energy electric fields fragment and identify them based on their mass-to-charge ratios.

A major plus point for this method is its speed: components can be identified in less than 90 seconds after entering the system. GC-MS is also extraordinarily sensitive – down to the picogram range – so it is possible to determine the exact composition of complex samples with extraordinary accuracy.