An Inductively Coupled Plasma Mass Spectrometer with Adjustable Vacuum Pressure

Abstract

The present invention relates to an inductively coupled plasma mass spectrometer with adjustable vacuum pressure, comprising: a first vacuum chamber, a second vacuum chamber, a third vacuum chamber, and a fourth vacuum chamber; the inductively coupled plasma mass spectrometer further includes: The first tuning part, the first tuning part is a pump, connected to the vacuum chambers of all levels, and adjusts the pressure of the vacuum chambers of the various levels; the second tuning part, the second tuning part makes the vacuum chambers of the various levels communicate with each other, Regulate the pressure between the various vacuum chambers. The invention also provides a method for adjusting the pressure of the vacuum chambers at each stage of the inductively coupled plasma mass spectrometer. The invention has the advantages of optimizing and reducing space charge effect, improving anti-mass spectrum interference and non-mass spectrum interference effect, optimizing ion transmission and the like.

Description

technical field [0001] The invention relates to the field of mass spectrometry, in particular to an inductively coupled plasma mass spectrometer with adjustable vacuum system pressures at all levels. Background technique [0002] Inductively coupled plasma mass spectrometer (abbreviation: ICP-MS), the ion source is inductively coupled plasma, the sample is converted into ions in the plasma flame, and the plasma formed by the working gas, sample, matrix and solvent is passed through the differential vacuum double cone or The three cones are extracted into the vacuum system. Double cone or triple cone realize transition from atmospheric pressure to vacuum, from high temperature to normal temperature. The first cone of the double cone is the sampling cone, and the latter cone is the skimmer cone; the first cone of the triple cone is the sampling cone, the middle one is the skimmer cone, and the latter is the super skimmer cone. [0003] The vacuum system of ICP-MS can be divi...

AI Technical Summary

Problems solved by technology

At present, the vacuum system in ICP-MS adopts a fixed design, which cannot be adjusted and optimized, thus causing the following defects:

[0004] 1. The optimal position of the sampling cone for ultrasonic molecular beam extraction cannot be adjusted and optimized, and cannot meet the requirements for the use of skimmer cones of various shapes and calibers;

[0005] 2. After the skimmer cone, the plasma ion beam is electrically neutral before it is non-electrically neutral, and the electric field in the channel of the skimmer cone is not easy to penetrate, and the effect of the electric field cannot significantly improve the transmission;

[0006] 3. There is an ion space charge effect behind the skimmer cone, resulting in a very low ion transmission efficiency;

[0007] 4. In the collision response mode, it will affect the pressure at all levels of the original vacuum system, and the conditions cannot be optimized, and at the same time affect the scope and effect of the collision response mode

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