Technical progress and development in the field of

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Analysis of technological progress and development in the field of chromatography

chromatographic analysis is one of the most active branches of analytical chemistry at present, and it is also an important means of material separation and analysis. Its application in the fields of environment, biochemistry, fine chemical product analysis and so on is increasingly common, and almost all fields involve the application of chromatography and its related technologies. From classical plate chromatography to column chromatography, from gas chromatography, high performance liquid chromatography, supercritical fluid chromatography to capillary electrophoresis and electrochromatography, they all play an important role in scientific research and industrial production

origin of chromatography

the ancient Romans used a piece of cloth or a piece of paper to analyze dyes and pigments. More than 100 years ago, German chemists improved this method to have better reproducibility and quantitative ability. This technology later developed into today's paper chromatography technology. In 1901, Russian botanists used calcium carbonate as adsorbent to separate plant pigments. Then in 1903, they first proposed a new method to separate plant pigments based on the principle of adsorption. In 1906, this method was officially named chromatography, but it did not attract attention because of its slow separation speed and low efficiency. Until 1931, German scientists used similar methods to separate more than 60 pigments such as carotene, and chromatographic methods were widely known and used

development and application of gas chromatography technology freight rates on various routes of Capesize ships have risen or fallen by less than 1

since the world first established practical gas-liquid chromatography in 1952, gas chromatography, as a representative of modern analysis and detection instruments, has developed into an industry with considerable production scale and formed a discipline with quite rich detection technology knowledge. Because of its high separation efficiency, fast analysis speed and good selectivity, gas chromatography is widely used in the fields of pollutant analysis in environmental samples, drug quality inspection, natural product composition analysis, determination of pesticide residues in food, quality monitoring of industrial products and so on. With the emergence of new gas chromatography instruments, detectors and data analysis methods, the application field of gas chromatography will be more and more broad

The combination of gas chromatography and other technologies has also developed very rapidly in recent years. It is mainly used in combination with mass spectrometry, spectrum, chemical reaction, computer, etc. Gas chromatography is an effective tool for separating complex mixtures, but it cannot qualitatively identify unknown substances; Mass spectrometry, spectroscopy and nuclear magnetic resonance are also effective tools to identify the structure of unknown substances, but the samples analyzed are required to be as simple as possible, rather than complex mixtures. Therefore, the combination of chromatography and these techniques is a recognized and effective tool to analyze the structure of unknown compounds in complex mixtures. The development in recent years is characterized by the direct combination of the two technologies, eliminating the steps of intermediate collection and condensation, so as to shorten the analysis time and reduce the amount of samples

organic mass spectrometers, magnetic mass spectrometers, quadrupole mass spectrometers, ion trap mass spectrometers, time of flight mass spectrometers (t0f), Fourier transform mass spectrometers (FTMS), etc. currently sold on the market can be combined with gas chromatography. With the continuous updating of interface technology, the interface equipment is smaller and simpler, and the shape is lighter. The function of GC-MS is more powerful. The resolution of GC-TOFMS can reach about 50m. GC-MS plays an important role in many fields of analysis, detection and scientific research, especially in the detection of many organic compounds and any kind of equipment. It is widely used in environmental protection, health, food, agriculture, petroleum, chemical and other industries

development and application of liquid chromatography technology

at the beginning of liquid chromatography technology, under the action of gravity, the central axis of the sensor will be placed on the upper section of the vertical central plane of the two columns of the reaction frame. It uses a large diameter glass column to transport the mobile phase with the liquid level difference at room temperature and atmospheric pressure, which is called classical liquid chromatography. Liquid chromatography is a kind of separation and analysis technology, which is characterized by using liquid as mobile phase, and the stationary phase can be in many forms, such as paper, thin plate and packed bed. The mobile phase of classical liquid chromatography flows slowly through the chromatographic column by gravity, so the particle size of the stationary phase cannot be too small. The separated samples are collected by classification and then analyzed, which makes the classical liquid chromatography not only low separation efficiency, slow analysis speed, but also complex operation. Until the 1960s. Develop particle size less than 10 μ M, and uses a high-pressure infusion pump and an automatic recording detector, which overcomes the shortcomings of classical liquid chromatography and develops into high-performance liquid chromatography

high performance liquid chromatography is the most widely used field in various chromatographic models at present. In the analysis of compounds, about 80% of compounds in the world, including polymer compounds, ionic compounds Thermally unstable compounds and bioactive compounds can be separated and analyzed by different modes of HPLC (such as normal phase HPLC, reverse phase HPLC, ion exchange chromatography and ion chromatography, volume exclusion chromatography, affinity chromatography, etc.)

high performance liquid chromatography is developed from gas chromatography and liquid chromatography. Its structure and operation process are relatively perfect. The new research and development of high performance liquid chromatography and its combined technology have been widely used in chemical production, pharmaceutical industry, food industry, biochemical industry, medical clinical testing, environmental monitoring and other fields. Compared with high performance liquid chromatography, many other detection methods have been repeatedly verified for a long time for their feasibility, accuracy, precision and efficiency, and are ultimately less stable, reliable and efficient than high performance liquid chromatography Efficiency is eliminated. It can be seen that high performance liquid chromatography is not only of great significance to the present, but also has a wide range of development prospects in the near future

1. Users are used to do simple tensile experiments, contraction experiments, etc. when purchasing

development and application of supercritical fluid chromatography technology

supercritical fluid chromatography is a chromatography method using supercritical fluid as mobile phase. Supercritical fluid refers to some substances that are neither gas nor liquid, and their physical properties are between gas and liquid. Supercritical fluid chromatography is a new chromatographic technology developed in the 1980s. It has the advantages that gas phase and liquid phase do not have, and can separate and analyze some objects that gas phase and liquid phase chromatography cannot solve. It is widely used and develops rapidly. According to industry insiders, about 25% of the total separation so far involves difficult substances, and satisfactory results can be achieved through supercritical fluid chromatography

supercritical fluid has extremely favorable physical properties for separation, which are just between gas and liquid. The diffusion coefficient and viscosity of supercritical fluid are close to that of gas chromatography, so the mass transfer resistance of solute is small, and rapid and efficient separation can be obtained. On the other hand, its density is similar to that of liquid chromatography, which makes it easy to separate and analyze substances with high relative molecular weight and thermal instability at lower temperatures. In addition, the physical and chemical properties of supercritical fluids, such as diffusion, viscosity and solvent force, are functions of density. Therefore, as long as the density of the fluid is changed, the properties of the fluid can be changed. From similar gas to similar liquid, there is no need to pass through the gas-liquid equilibrium curve. Supercritical fluid chromatography is widely used in environmental protection, medicine, food, agriculture and other fields

Development and application of capillary electrochromatography

capillary electrochromatography is a new separation technology developed on the basis of capillary electrophoresis and microcolumn high performance liquid chromatography. Due to technical limitations, the research of capillary electrochromatography did not develop rapidly until the 1990s

at present, capillary electrochromatography plays a leading role in the research of drug analysis, focusing on the separation of drug-related impurities and chiral drugs, and the analysis objects are mainly neutral drugs and polycyclic aromatic compounds. With the continuous improvement and improvement of capillary electrochromatography technology, it will be applied in biotechnology, environmental protection, agricultural chemistry, fine chemical products, food industry and other fields. According to the current development momentum of capillary electrochromatography, CEC, as a developing separation technology, will have a wider application prospect in the foreseeable future

since the establishment of chromatography, it has developed rapidly not only in the development and improvement of chromatographic basic theory, new separation mode, new stationary phase equipment, chromatography and capillary electrophoresis instruments, but also in its practical application. In terms of chromatographic column types, classic chromatographic columns are widely used at present. Capillary column is very suitable for trace analysis, with fast analysis speed and less sample consumption. It is one of the development directions of chromatographic column types in the future. It can be predicted that chromatographic technology will develop in the direction of combining with other technologies, high precision, high sensitivity and miniaturization in the future

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