A dual-polarity ion mobility spectrometer for capturing hyper-fast chromatographic peaks
Year: 2025
Type: article
Abstract: • Dual drift tube IMS for capturing fast chromatographic peaks with 140 ms full width at half peak maximum. • Hyper-fast GC-IMS with limits of detection in the low ppb v range and high IMS resolving power of R P = 60 at 120 °C. • Hyper-fast GC-IMS with 30 s GC run time including cooling. • Ion source with minimum effective detector volume of 40 µL. For higher analytical performance, ion mobility spectrometers (IMS), especially when analyzing complex mixtures, are often coupled with gas chromatographs (GC). However, analysis time remains a critical parameter in gas chromatography. Therefore, a hyper-fast GC is a promising approach for GC-IMS to combine highest sensitivity of IMS with increased peak capacity while allowing for rapid analysis within the double-digit second range. For simultaneously recording of both ion polarities, a new dual drift tube IMS in axial configuration has been developed that is particularly designed for resolving even hyper-fast GC peaks. Key is a directed sample gas flow through the ionization region giving a small effective detector volume. To avoid condensation of the sample gas, the IMS is isothermally heated to 120 °C. A drift tube length of only L D = 41 mm with a drift voltage of U D = 2.7 kV leads to an IMS repetition rate of 100 Hz and high resolving power of R p = 60, even for ions with low reduced ion mobility down to 0.43 cm 2 V -1 s -1 . This setup can resolve very short GC peaks with full width at half maximum of only 140 ms. For demonstration, two different hop varieties and a mixture of explosives were analyzed within a short time of just 20 s.
Source: Journal of Chromatography A
Institution: Leibniz University Hannover
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,040
OpenAlex ID: W4408991206