Method for controlling mass analysis device by utilizing triangular wave signals

Abstract

The invention relates to a method for controlling a mass analysis device by utilizing triangular wave signals. The method comprises the following steps of: (1) arranging a control system comprising a laser, a vacuum cavity, an optical window, a sample target, a cylindrical ion trap, a charge detector, a mechanical pump and a triangular wave signal generator; (2) dropwise adding a sample onto a silicon wafer and fixing the silicon wafer on the front face of the sample target; (3) vacuumizing the vacuum cavity, filling an inertial buffer gas in the vacuum cavity and regulating the air pressure; (4) irradiating laser emitted from the laser to the back face of the sample target through the optical window and generating sample ions by utilizing a laser induced sound wave desorption method; (5) enabling the sample ions to enter a ring electrode through a gap between a cover electrode and the ring electrode, selecting an embarment mode for the triangular wave signal generator, regulating an embarment voltage and embarring the sample ions in the cylindrical ion trap; and (6) selecting a scanning mode for the triangular wave signal generator, throwing the sample ions which are embarred in the cylindrical ion trap and have mass-to-charge rate more than a set threshold out of the cylindrical ion trap, and detecting the sample ions by the charge detector. The method disclosed by the invention is widely applied to measurement of mass ingredients of substances.

Description

technical field [0001] The invention relates to a control method, in particular to a method for controlling a mass analysis device by using a triangular wave signal. Background technique [0002] Mass spectrometer is a tool for measuring the quality of substances. It has the advantages of sensitivity, speed and accuracy, and plays an important role in the research of modern life sciences. The core part of a mass spectrometer is a mass analysis device, which mainly includes an ion trap and a quadrupole. Ion traps include two-dimensional linear ion traps and three-dimensional rotating ion traps. The two-dimensional linear ion trap includes electrode pairs in the three directions of x, y, and z. When detecting sample ions, the electrode pairs in the x and y directions are connected to the corresponding RF AC voltage and a DC voltage is applied to the electrode pair in the z direction. This traps the sample ions in the z-axis. The three-dimensional rotating ion trap can trap ...

AI Technical Summary

Problems solved by technology

The RF AC signal has different waveforms, the most commonly used is the sinusoidal signal. Since the sinusoidal signal is restricted by the discharge voltage, the movement frequency of the sample ions is also limited by the sinusoidal signal voltage, which affects the resolution of the mass analyzer.

A control method different from the traditional sinusoidal signal has also been proposed. For example, the digital ion trap proposed by Ding Li et al. can also achieve the same function as a sinusoidal signal by providing a rectangular wave signal, but the rectangular wave signal has a large mutation, which is likely to cause signal distortion.

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