Shanghai chromatography headspace sampler

Headspace sampling technology is a convenient and fast sample pretreatment method in gas chromatography, suitable for the analysis of volatile components. Its principle is to place the sample to be tested in a closed container, heat and raise the temperature to evaporate the volatile components from the sample matrix, reach equilibrium in the gas-liquid (or gas-solid) phase, and then directly extract the top gas for chromatographic analysis to test the composition and content of volatile components in the sample.

Shanghai chromatography headspace samplerThe use of headspace injection technology can eliminate lengthy and tedious sample pretreatment processes, avoid interference from organic solvents in analysis, and reduce contamination of chromatographic columns and injection ports. This instrument can be connected to various models of gas chromatographs both domestically and internationally

working principle:

In the analysis and detection process using headspace gas chromatography, the headspace sampler used is a sample pretreatment instrument. The working principle of headspace gas chromatography is to place the sample to be tested in a closed container, heat and raise the temperature to evaporate the volatile components from the sample matrix, reach equilibrium in the gas-liquid or gas-solid phase, and directly extract the top gas for chromatographic analysis to test the composition and content of volatile components in the sample. The use of headspace injection technology can eliminate lengthy and tedious sample pretreatment processes, avoid interference from organic solvents in analysis, and reduce contamination of chromatographic columns and injection ports.

Headspace sampler workflow

Sample heating injection - pressurization - sampling - sample filling into quantitative tube - six way valve switching injection - starting workstation to start sampling data, etc

The method of headspace injection:

1.Manual injection (water bath method)

After heating the sample, use a syringe to extract it directly for chromatographic injection

2.Gas tight needle injection

The sample reaches thermal equilibrium by heating the airtight needle to extract the sample and inject it into the gas chromatograph

3.Quantitative ring pressurization system

After the sample is heated to equilibrium, it is pressurized into the quantitative loop and injected into the gas chromatograph through valve control

4.Headspace sampler

Using instruments to achieve headspace injection through blowing and constant pressure

Comparing four injection methods, headspace analysis is an ideal sample purification method Traditional liquid-liquid extraction and SPE involve dissolving the sample in a liquid, inevitably leading to some co extracted substances interfering with the analysis Moreover, the purity of the solvent itself is also an issue, which is particularly important in trace analysis Using gas as a solvent can avoid unnecessary interference, which can prevent the loss of volatile compounds during solvent removal and reduce the noise caused by co extraction. It has higher sensitivity and analysis speed, less harm to analysts and the environment, and is easy to operate. It is an analytical method that meets the requirements of "green analytical chemistry".