In 1978, Still invented flash chromatography, published in J.O.C, from which the flash method was established. Flash column is derived from open glass column chromatography and is mainly used for the separation and purification of natural products and organic synthesis products. The classical flash chromatogram consists of a glass column, a liquid storage bottle, and a compressed air regulating valve. With low cost, it is easy to observe, but the pressure is low and easy to break.
Many laboratories now place a pressurized ball on top of a glass column, which is a similar product and forms a classic flash chromatography system after improved. It consists of the infusion pressure tank, flows regulating valve, flashes pre-packing column and sample loading device. The equipment is compact, easy to use, with high pressure and high reproducibility. The classic flash chromatogram is still pressurized with air pressure, the pressure range is about 0-7 bar, the column length is about 15 cm, and the filler particle size is 40-60 Torr. The solid and liquid can be loaded and the fraction collected by hand.
Development
Over 20 years of development, the flash column has been widely used as a conventional purification separation device. The narrowly defined flash column refers to a low-pressure short-column preparative liquid chromatography system that uses compressed gas to generate pressure and accelerate the elution rate of the mobile phase. The generalized flash column system refers to the medium-low pressure liquid chromatography system of all infusion methods.
Over 20 years of development, the flash column has been widely used as a conventional purification separation device. The narrowly defined flash column refers to a low-pressure short-column preparative liquid chromatography system that uses compressed gas to generate pressure and accelerate the elution rate of the mobile phase. The generalized flash column system refers to the medium-low pressure liquid chromatography system of all infusion methods.
Recently, because of the intensification of scientific research competition and the increase of laboratory labor costs, higher automation and separation speed are required, resulting in automated flash columns, chromatography pumps, detectors, automatic fraction collectors and workstations. Some also have a gradient elution system, a column switching system, and an automatic sample introduction system. The conditions can be optimized to achieve unmanned operation, which greatly reduces labor costs and speeds up development.
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