high performance liquid chromatography abbr., HPLC (rus. хроматография, высокоэффективная жидкостная abbr., ВЭЖХ) — an effective chromatographic technique to separate complex mixtures of compounds, which is based on various adsorption properties of their components in relation to a sorbent.

Description

A distinctive feature of HPLC from other liquid chromatography methods is the high pressure applied while the mobile phase goes through the column (up to 250 bar) and microgranular sorbent (about micron particle size) to separate a substance in a column from 2 to 30 cm long.

Depending on the separation nature, there are partition chromatography, ion exchange chromatography, adsorption chromatography and size-exclusion chromatography. In practice, the best known is partition (reversed phase) chromatography.

Chromatographic separation is performed using a chromatograph. The instrument consists of a pumping system, a sampling valve, a column, a detector and data acquisition and data processing unit (see Fig.).The pumping system is responsible for the continuous flow of the mobile phase through the column. The sample is injected through a sampling valve (or injector), the separation occurs in a column with a special sorbent, which is usually a chemically modified surface of silica gel grains.

A chromatogram serves as the graphical representation of separation results, which shows the dependence of the detector signal on the time elapsed. Each substance is shown as a peak with the area being directly proportional to the concentration of the substance in the mixture.

Illustrations

Simplified chromatograph design.
Simplified chromatograph design.

Author

  • Streletskiy Alexey V.

Source

  1. H. Henke. Preparative Low Pressure Liquid Chromatography. — Vogel Business Media GmbH & Co. KG 2011. — 828 P.

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