Method And Apparatus For Automatic Chromatography Of Thin-Layer Plates

Abstract

A method for the automatic chromatography of thin-layer plates for thin-layer chromatography with a development chamber 1 in which a thin-layer plate D is completely enclosed, sealed-off and isolated from the external environment. In the development chamber, a front space containing an inner atmosphere is located on the front face of the separation layer of the thin-layer plate. The depth of the front space is about 2 mm and a maximum 3 mm. An inlet is provided at one end of the front space and an outlet is provided at the other end of the front space. During the chromatographic development, a stream of gas of particular composition determined by the user is created throughout the entire front space, the entire inner atmosphere being set in motion, without stagnant or stationary gas phase.

Description

[0001]The present invention relates to a method for automatic chromatography of thin-layer plates in the field of thin-layer chromatography according to the preamble of patent claim 1 and an apparatus for carrying out this method according to the preamble of patent claim 8.[0002]Thin-layer chromatography is a separation method for analyzing the composition of liquid samples consisting of two essential steps:[0003]1) The application of the sample to the separation layer of a thin-layer plate, usually a silica gel layer (the so-called stationary phase);[0004]2) The chromatographic development, wherein usually the lower end of the thin-layer plate is brought into contact with an eluent which migrates upwards at a certain speed in the separation layer by capillary forces (the so-called mobile phase).[0005]During the chromatographic development, the molecules contained in the sample are carried by the eluent through the separation layer. Due to their different chemical properties, differ...

AI Technical Summary

Benefits of technology

The patent is about improving the way chromatography is done by using thin-layer plates. The new invention makes it possible to better control important factors that affect the development process, such as the properties of the separation layer and the composition of the inner atmosphere. This makes the chromatography faster, easier, and more accurate.

Problems solved by technology

A major shortcoming of this simple method is the poor reproducibility of the resulting chromatograms, making comparisons of results on different plates and at different locations difficult.

However, it is not sufficient to carefully adjust the inner atmosphere before the start of the chromatographic development, since it constantly changes in the course of the chromatographic development, in particular at the interface with the thin-layer plate due to the evaporation of the eluent.

However, this represents a complex infrastructure, with a fairly large volume, in which a chaotic and hardly controllable gas flow is generated.

Diffusion phenomena, however, are particularly slow, which may result in inhomogeneities in the composition of the inner atmosphere, particularly at the interface between the plate and the remainder of the volume.

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