Quantitative mass spectrometry by orthogonal projection method with periodic signal of electrostatic ion beam trap

In this paper, orthogonal projection method (OPM) is introduced which could perform quantitative mass spectrometry with signal of electrostatic ion beam trap (EIBT). In order to acquire periodic current signal, a model of EIBT with cylindrical-detector is set up to simulate ions oscillatory motion. Where after, OPM is introduced and applied for quantitative mass spectrometry. It shows that quantitative MS with high precision could be obtained by OPM with sampling time short as 200 μs. Comparing with FFT, the mass spectrometry performed by OPM is characterized by higher precision and much shortened sampling time. OPM mass spectrometry is influenced by several factors, including the length of sampling time, mass detecting interval δM, tested ion mass and its location in the mass detecting interval, which are discussed systematically. The OPM results show that, the effective sampling time for quantitative MS should be prolonged when the tested ion mass is increased or the mass detecting interval is decreased. The shortest effective sampling time T90S and the longest effective sampling time T90L are all proportional to M3/2/δM, and the relation of which is specified by linear regression.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (112 K)Download as PowerPoint slideResearch highlights▶ EIBT model is set up to generate signal for mass spectrometry. ▶ Orthogonal projection method (OPM) performs quantitative MS with high precision. ▶ Sampling time of OPM is quite shortened comparing with FFT. ▶ Effective sampling time is proportional to M3/2/δM.