TLC is a leader in matters of quantitative and semi-quantitative analysis of complex pharmaceutical, natural, biomedical, technological, chemical and many other substances.TLC is also the most accessible method of mass analysis of virtually all classes of substances.
This method of separation and analysis of multi-component systems are widely used in the laboratories of very different specificity and direction: sanitary-epidemiological, veterinary, agrochemical, research, forensic, and the stations of plant protection in the centers of standardization and Bureau of Forensic Medicineexamination.
main advantages of thin layer chromatography, based on the movement of eluent (solvent, analyte) in the sorbent layer by the so-called capillary forces are the simplicity and easiness of the chromatographic process, the high degree of precision of the analysis and the relatively low cost of the necessary equipment.
TLC, having a high degree of sensitivity (low detection threshold) and selectivity makes it possible to determine the substance of 10-20 mg up to 7%, which is very high.TLC can be adsorption and distribution types.The most widely used is the first option.The method
TLC solvent is in motion in a layer of sorbent material and the spatial distribution of the various components according to their individual characteristics and properties.The fact that the molecules of different composition and structure of the adsorbed (deposited) on the surface of the solid chromatographic plate differently.Therefore, complex multi-component systems are gradually separated into individual components.
Moving at different speeds along the sorbent bed, separate, already separated, constitute the components of the chromatogram.Each color spot corresponds to a particular chemical.The colorless substance with the ultraviolet light, under the influence of a plurality of compounds which are starting to fluoresce, or treated special staining reagent.
Among modern analytical methods especially stands out gas-liquid chromatography.This method of separation and analysis characterized by the use as a sorbing agent special nonvolatile liquid, wherein the powdered ceramic material is wetted.And as the driving medium here are various inert gases.This method is most effective for the study of complex mixtures that contain hundreds of different components.
Another modern method of studying the composition of complex materials is a liquid chromatography.The principal feature of this method is the separation of the individual components by utilizing differences in their distribution among the mobile (eluent) and fixed (sorbent) phases.This method is most often used in the analysis of various organic compounds (food additives, pesticides, various toxins, etc.).Also, such a chromatographic method is used to study the quality control of pharmaceutical products, the determination of steroids in biological fluids, and other amino acid analysis.
