Thermoelectric liquid chromatography (usually referring to high-performance liquid chromatography, HPLC) is an important analytical technique.

1. Sample introduction and mobile phase drive: After the sample enters the system through the injector, the mobile phase (liquid) is continuously transported through the chromatographic column by a high-pressure pump. This is the starting point of the entire process, ensuring that the sample can be accurately carried into the separation stage.

2. Separation mechanism core - interaction differences: The chromatographic column contains a stationary phase, and different components in the sample are separated due to differences in the strength of their interactions (such as adsorption, distribution, etc.) with the stationary phase and mobile phase, resulting in differences in retention time in the chromatographic column. For example, in reverse phase chromatography, components with strong lipophilicity are more likely to remain on the hydrophobic groups of the stationary phase, distribute/stay in the stationary phase for a longer time, flow out of the chromatographic column slower, and have a longer retention time; And components with weak lipophilicity have weak interaction with the stationary phase, are easily washed away by the mobile phase, have a short residence time in the chromatographic column, flow out of the column earlier, and have a short retention time.

3. Detection and signal conversion: The separated components enter the detector in sequence, and the detector converts the component signals into electrical signals. Common detectors include UV visible detectors, fluorescence detectors, mass spectrometry detectors, etc., which can detect compounds with different characteristics.

4. Data processing and result presentation: The data processing system records and processes these electrical signals, generates chromatograms, with retention time on the x-axis and detector response values (peak height or peak area) on the y-axis, in order to perform qualitative and quantitative analysis of each component in the sample.

Advantages of Thermoelectric Liquid Chromatography:

1. High efficiency separation capability: The selectivity and high efficiency of liquid chromatography columns enable various components in the sample to be effectively separated in a very short period of time. Its filler has high uniformity and stability, which can provide high column efficiency and resolution, and can analyze multiple components simultaneously and accurately determine their content. The separation efficiency can also be optimized by changing the composition, pH value, temperature and other conditions of the mobile phase.

2. High selectivity: By selecting appropriate combinations of stationary and mobile phases, highly selective separation can be achieved. The distribution coefficients of different compounds between the stationary phase and the mobile phase are different, and targeted selection can be made based on the characteristics of the sample to be tested. And modern liquid chromatographs are often used in conjunction with other analytical instruments, such as mass spectrometers, to further improve selectivity and accuracy in qualitative and quantitative analysis.

3. High sensitivity: Equipped with high-sensitivity detectors such as UV visible light detectors, fluorescence detectors, evaporative light scattering detectors, etc., it can detect extremely low concentrations of compounds, suitable for trace analysis and ultra trace analysis. It is very important for monitoring pollutants in environmental samples and analyzing trace components in drug development.

4. High degree of automation: Most HPLC systems are equipped with automated components such as automatic samplers and automatic cleaning devices, which can automatically complete the entire process of sample injection, analysis, data processing, and result reporting, reducing human errors, improving the repeatability and comparability of experiments, and greatly reducing the burden on researchers.