Design and development of a scanning magnet for high-resolution mass spectrometry

The magnets play a crucial role in sector mass spectrometers, directly influencing the resolution, sensitivity, and stability of these instruments. This study is based on the design requisites for high-resolution scanning magnet, alongside the optical layout schematics for mass spectrometer instrumentation. The analysis is conducted on the design parameters encompassing magnetic structure, field quality, and response dynamics. Utilizing Opera-3D simulation software, optimization designs are executed for the magnetic structure and performance, resulting in a magnet design exhibiting commendable attributes such as response time, magnetic field distortion characteristics, field range, linearity, and homogeneity. Following the completion of magnet fabrication and assembly, comprehensive evaluations of magnetic field performance and instrument testing are conducted. Results demonstrate good magnetic field linearity and minimal eddy current distortion, with a magnetic field homogeneity reaching up to ±0.05 % within the desired field region. The magnet exhibits versatility across a scan range spanning 7 to 238 u, with a scanning speed of 140 ms. Sensitivity and resolution tests, conducted using In-115, validated the magnet's compliance with the stringent design requirements of high-resolution mass spectrometry scanning magnets.