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Understanding the Role and sync of GC Capillary Column and its Detector

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Quadrex Corp
Understanding the Role and sync of GC Capillary Column and its Detector

Gas chromatography is an integral part of applied chemistry. Chromatography as such is a process that is used to separate different ingredients of a mixture. The volatility and polarity of the liquids play a major role in this technique. Two types of phases are used one is the mobile phase and the other is the stationary phase. The mixture does some interactions with the surface of the material of the stationary phase and depending upon these interactions only the results differ. The stationary phase is kept in a capillary column. Although there is one more type of column available known as packed columns which are comparatively cheaper and easier to use than capillary columns if you have a complex mixture your first choice will be capillary column only. Even though these are expensive as compared to the packed columns, the resolution provided is comparatively far better as compared to packed columns. GC Capillary column has the characteristic that on the inner surface the stationary phase is coated and it is not packed in the cavity. If you want to check the individual molecular components of the sample capillary GC columns are to be used. The best way to determine the chemical constituents of the sample and to get the analytical data for the impurities is to use GC with capillary columns. The technique is widely used since 1979 and has been upgraded several times since then. The column is the most important part of the chromatography machine as the inert and non–adsorbent stationary phase is kept in this only.  Fused silica and quartz are the best materials from which the capillary columns are made. The constriction is done with stainless steel and borosilicate glass. Gas chromatography has a wide range of applications in industries and fields like the food and beverage industry, Agricultural sciences, pharmaceutical analysis, petroleum industry, Chemical warfare, Medial applications, Forensic sciences, etc.

How Flame photometric detector for GC is used?

Metals have the ability to emit light when they are introduced to the flame. If we check the wavelength of the color we can deduce which element is there and if we want to quantify the amount of element we can check the color of the flame. We can use the flame photometer for both quantitative and qualitative analysis of elements present in a mixture. As each and every element have their signature emissions we can easily detect them. Both alkaline and alkali metals can be detected by this instrumentation. The fun fact is that even the minutest of concentrations can be detected. Further, flame photometry has advanced applications with gas chromatography. Mainly materials and compounds containing phosphorous or Sulphur like chromium, boron, arsenic, tin, etc. are detected by the flame photometric detector for GC. A hydrogen-rich atmosphere is there in which burning takes place, and we have to keep in mind that the carrier gas has low levels of water and oxygen impurities. As water and oxygen have a high affinity to interact with the stationary phase, subsequently problems like column bleed, high baseline noise can occur which can result in a significant reduction in sensitivity of the analyzer, and life expectancy of the column is also reduced.  Another factor to be contained are hydrocarbon impurities which can wreck the main instruments. So to contain the above-mentioned problems desolvation is done to the sample where metal particles are dehydrated by using flame and solvent is evaporated. This leads to the vaporization of solvent. After this atomization is done where all the atoms of a chemical substance are separated. Post atomization excitation is to be conducted when atoms achieve higher entropy after absorbing high amounts of energy.  As the matter has a tendency to lose the agitated state when the atoms come back to their normal state, they emit radiation of a specific wavelength which helps in identifying the chemical. This detection is done by the flame photometric detector.

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