Ion mass screening device in time-of-flight mass spectrometry

Abstract

The invention relates to a mass spectrometry instrument, in particular to an ion mass screening device in a time-of-flight mass spectrometer, which includes a mass analyzer, and the mass analyzer includes a vacuum cavity, a field-free flight area located in the vacuum cavity, and a grid electrode , a microchannel plate and a Faraday disk; an ion mass screening electrode is arranged in the area between the two metal grids of the grid electrode; all adjacent plate structure electrodes of the ion mass screening electrode are respectively applied with opposite polarity, pulse Pulse voltages U1 and U2 with the same width and synchronous timing. The ion mass screening device in the time-of-flight mass spectrometer of the present invention can selectively filter the ion mass reaching the ion detector of the microchannel plate, eliminate the interference of high-intensity ion background ions and reaction reagent ions on the microchannel plate detector, and can not only The dynamic range of the instrument is effectively increased, the detection sensitivity is improved, and the service life of the ion detector of the microchannel plate can be greatly improved.

Description

technical field [0001] The invention relates to a mass spectrometry instrument, in particular to a time-of-flight mass analyzer, in particular to an ion mass screening device in a time-of-flight mass spectrometer. Background technique [0002] Time-of-Flight Mass Spectrometer (TOFMS) is a commonly used mass spectrometry technique, which determines the The mass-to-charge ratio can be used to realize the qualitative analysis of the analyte. TOFMS has simple structure, high resolution and sensitivity, wide mass range, and has microsecond-level fast response speed and full-spectrum simultaneous measurement capability. Therefore, it is widely used in ecological environment, life and health, material science, biomedicine, process analysis, etc. field has been widely used. In the detection process of actual samples, when TOFMS uses chemical ionization (Chemical Ionization, CI) source, electron impact ionization (Electron Ionization, EI) source, inductively coupled plasma ionizati...

AI Technical Summary

Problems solved by technology

However, since TOFMS does not have the mass screening capability of quadrupole mass spectrometer and ion trap mass spectrometer, all ions will be received, amplified and output by the Micro Channel Plate (MCP) ion detector, which will easily cause MCP ion The saturation of the detector not only affects the detection of weak ion signals and generates high background noise, but also affects the service life of the MCP ion detector

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