HPLC (high-performance liquid chromatography) and GC (gas chromatography) are widely used separation techniques in pharmaceutical industries, industrial laboratories, and academia. High-performance liquid chromatography has applications in the field of pharmaceuticals, polymers; life sciences, etc. Gas chromatography has applications in pharmaceuticals, petroleum, petrochemical industry, etc.
HPLC and GC operate on the same principle but with different results. In general, chromatography is the process of separating parts of a mixture by passing it through a gaseous column or liquid solution and generating data for the scientist to analyze.
HPLC and GC are used in analytical chemistry to analyze samples and determine what the sample contains, its techniques are effective for the separation of analytes and it is a multipurpose and very well-accepted chromatographic technique utilized for the separation of complex mixtures. HPLC and GC are chromatography techniques based on the physical state of the mobile phase. HPLC uses liquid as the carrier and GC uses gas as the carrier.
HPLC and GC techniques are used for identification and quantification purposes but for different intents as their functions and applications are different further HPLC and GC are based on the principle where the compound is subjected to the surface or within a solid or liquid stationary phase by isolating it with the help of the mobile phase. The selection of instruments is purely based on the nature of the sample and the requirement of the sample.
The following table summarizes the differences between HPLC and GC techniques:
HPLC is a technique in analytical chemistry used to identify, separate, and quantify each component present in the mixture. The liquid solvent contains the sample mixture which passes through the columns filled with a solid adsorbent material. The component present in the sample interacts marginally differently with the adsorbent material, causing different flow rates for different components which leads to the separation of components as they flow out of the column.
The common mobile phases which are used, include any miscible combination of water with various organic solvents (the most common are Acetonitrile and methanol).
Gas chromatography is the technique used in separating compounds in a mixture by injecting a gaseous or liquid sample into the mobile phase which is called the carrier gas and passing the gas through a stationary phase.
In GC there is a column through which the sample passes in the vaporized phase carried along with the flow of continuous gases like inert or non-reactive gas. The components of the sample pass through the column (enclosed within a temperature-controlled oven) at different rates called the stationary phase. As the chemical exists from the column it is detected and identified electronically.
GC is an analytical technique and has several advantages like ease of operation, speed of analysis, separation of volatile compounds, relatively sharp peaks observed with good resolution, quantitative results, and separation of complex mixture components in a reasonable time.
HPLC is an analytical technique and has advantages like the accurate process of separation of analytes, simple data analysis, robust methods, retention time, and area of samples are precise and can be used for a wide range of compounds.
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