Collaboration between El-Mul technology, MSC and Acqiris contributing to an innovative high dynamic range TOFMS technology

June 2, 2024

Learn more about High Dynamic Range Data Acquisition System for TOFMS, at ASMS24

Poster session ThP 519

Thursday, June 6 – Session Instrumentation: New Concepts – 10:30 – 11:30 am

Pierre-François Maistre from Acqiris and Amit Weingarten from El-Mul Technology have presented a poster resulting from the collaboration between El-Mul technology, MSC and Acqiris.

Poster Summary

Modern Time-of-Flight Mass Spectrometers (TOFMS) generate strong repetitive signals, with maximal intensity reaching up to l=1E+4 ion/pulse/peak which intensity stresses the dynamic range of detectors and Analog-to-Digital Converters (ADC). We present a high dynamic range data acquisition system employing several key components: an M-TOF hybrid detector by El-Mul, featuring a linear signal response up to 10 V and a long lifetime with peak widths under 1 ns; a switching dual gain amplifier with a synchronizing clock by MSC; and a single channel SA230P ADC by Acqiris. By leveraging the repetitive nature of the signals, the amplifier gain alternates over time, and signals are stitched online using a CPU. This system efficiently counts individual ions above a threshold with an 80% duty cycle, while maintaining a linear response for intense signals for l up to 5E+3, without degrading peak shape or mass accuracy.

The M-TOF detector (El-Mul) utilizes an ion-to-electron converter, a fast scintillator, and a high-speed photomultiplier tube (PMT)/hybrid photodetector (HPD). The signal acquisition SA230P board (Acqiris) offers a 4 GS/s sampling rate, 14-bit vertical resolution, and a fast PCIe bus. A home-built GC-MRT system (MSC) incorporates a custom dual gain switching amplifier.

The amplifier switches between gains of x1/3 and x10 are time alternated at 8:2 shot pattern over 1 ms cycles. Gas Chromatography-Mass Spectrometry (GCMS) analyses were conducted across a wide range of sample injections, from 1 pg to 10 ng per species, using a 76-component MegaMix sample (Restek). Mass drift is compensated using a constant leak of PFTBA to verify mass accuracy and signal linearity, achieving a dynamic range DR>3E+6/s and l up to 5E+3.