Gas chromatography-low temperature plasma ion source mass spectrometer combined device

Abstract

The invention discloses a gas chromatography-low temperature plasma ion source mass spectrometer combined device. The gas chromatography-low temperature plasma ion source mass spectrometer combined device is characterized by comprising a gas chromatography, a mass spectrometer, a metal electrode and an insulating cavity, a first cha channel, a second channel, a third channel and a fourth channel which are communicated are sequentially formed in the periphery of the insulating cavity, the first channel is communicated with the capillary pillar outlet of the gas chromatography, the second channel is communicated with a gas carrier and gas outlet end, the third channel is communicated with or aligned with a sample feeding port of the mass spectrometer through an insulating medium tube, the fourth channel is connected with the metal electrode, one end of the metal electrode enters the insulating cavity, the other end of the metal electrode is connected with a power supply device, and airtight assemblies are arranged in all the channels respectively. The gas chromatography-low temperature plasma ion source mass spectrometer combined device has the advantages that diffusion of a sample separation peak can be reduced, and the ionization efficiency of a sample is improved.

Description

Technical field [0001] The invention relates to the technical field of low-temperature plasma ion sources, in particular to a gas chromatography-low-temperature plasma ion source mass spectrometer combined device. Background technique [0002] Mass spectrometer is currently a widely used chemical analysis instrument. Its basic principle is to ionize the components in the sample in the ion source to generate charged ions with different mass-to-charge ratios, and then use electric or magnetic fields to The ion movement of the mass-to-charge ratio produces different effects, thereby realizing the detection of substances. [0003] The ion source provides sample ions for the mass spectrometer, and the key lies in ionization technology. Among them, the low temperature plasma ion source represented by the dielectric barrier discharge ion source (DBDI) is a type of soft ionization ion source used in mass spectrometers, and its main feature is that it can generate stable low temperature pl...

AI Technical Summary

Problems solved by technology

[0005] However, the above-mentioned existing low-temperature plasma ion source mass spectrometer and gas chromatograph combined device still have the following problems: 1) The outlet pressure of the gas chromatographic capillary column is atmospheric pressure, so compared with the low vacuum of the conventional gas chromatographic capillary column Conditions, the concentration of the separated gaseous sample will be greatly diluted at the outlet, resulting in severe diffusion of the separation peak; 2) The gaseous sample and the low-temperature plasma beam only meet with a limited cross-sectional area at the intersection, so the amount of ionized sample is limited , resulting in incomplete ionization; 3) The sample ions generated by ionization enter the inlet of the mass spectrometer through the gas flow path, and this ion transmission method will cause a large ion loss during the transmission process

The above three problems existing in the existing gas chromatography-low temperature plasma ion source mass spectrometer combination device will comprehensively limit the number of ions that enter the mass spectrometer for detection, thereby limiting the detection limit of the mass spectrometer.

Images