Prospects of high-speed countercurrent chromatography
in recent years, the selection range of solvent systems has become wider and wider. Some people have proposed using supercritical carbon dioxide as the mobile phase to separate compounds by taking advantage of its incomparable advantages of other solvents, such as high diffusivity, low viscosity, fluid characteristics and environmental friendliness. Others have proposed the possibility of using refrigerant as the mobile phase. It was also suggested that the use of three-phase solvent system in high-speed countercurrent chromatography is an important part of accelerating the transformation and development of economy and society. Lianxun securities can emphasize the good separation of samples with wide polarity range. At present, the three-phase solvent is only used for the separation of standard mixture, and has not been used for the separation of specific natural products. It is believed that further development will have great application prospects in the separation of complex natural products and drugs
ph zone countercurrent chromatography is a newly developed preparative chromatography technology, which can increase the loading capacity of samples by more than 10 times, and even substances with very low content can be highly concentrated. It is to add a pair of reagents -- retention agent and eluent to the stationary phase and mobile phase. The retention agent is used to retain the components in the sample in the column. When the mobile phase containing eluent passes through the stationary phase at a certain flow rate, the acid-base reaction finally reaches equilibrium. The concentration ratio of the retention agent in the two phases is used to scale the distribution coefficient of the retention agent. The difference between the distribution coefficient of the solute and the scale value determines the peak time of the solute, and the separation is realized according to the pKa and hydrophobicity of different components. Its chromatographic peaks are highly concentrated rectangular peaks with little overlap, which are connected one by one, much like the chromatographic peaks of alternative chromatography
ion pair countercurrent chromatography is to add appropriate ligands to the stationary phase to improve the retention value of solutes in the stationary phase and improve the peak resolution. It has been widely used in the separation of peptide components, alkaloids and amino acids in natural drugs
dual mode countercurrent chromatography (duccc), that is, two phases flow simultaneously from both ends of the spiral tube and flow out from the corresponding ports at the same time, forming a real reverse convection. Compared with conventional HSCCC, duccc has faster separation speed and higher separation efficiency, so it is unnecessary to predict the retention time and partition coefficient of solute, which reduces the tedious selection of solvent. This technology can be applied to protein separation
the combination of HSCCC and other technologies such as mass spectrometry is also a current research hotspot. It combines the diversity of HSCCC separation with the high sensitivity detection and structural analysis characteristics of mass spectrometry, and further expands the demand to the economic field. The prospect is very promising. In order to overcome the shortage of relatively lagging theoretical research of HSCCC, many researchers are engaged in theoretical research, trying to establish a perfect theoretical basis to guide the selection of solvent system, in order to make HSCCC develop from a separation technology to a separation science as soon as possible
hsccc is a unique liquid-liquid distribution chromatography technology without solid carrier. It is a practical separation and preparation technology that can realize continuous and effective separation. It can use a variety of solvent systems to separate samples in any polarity range. It can realize the analysis and separation from micrograms and microliters to hundreds of milligrams, and can also purchase multiple sets of equipment at the same time to produce gram level preparation and purification, It is suitable for the intermediate stage separation of a large number of crude samples that have not been strictly treated, and can also be used in conjunction with mass spectrometer, infrared spectrometer and other analytical instruments for high-purity analysis. Its application prospect is very broad
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