Improving duty cycle in the Folded Flight Path high-resolution time-of-flight mass spectrometer

Abstract

The duty cycle is a critical parameter affecting the sensitivity of analyses by Time-of-Flight Mass Spectrometers with Orthogonal Accelerators (OA-TOFMS). Improving the duty cycle becomes especially critical for the analytical performance of high-resolution TOFMS (HR-TOFMS) with elongated ion paths, such as based on multi-reflecting types of mass analyzers. Currently used methods for improving the duty cycle are based on accumulating ions in various trapping devices between push pulses. These methods do not always provide the best analytical results, may create conditions for secondary reactions, and require adjusting acquisition conditions to maximize the effect. The Encoded Frequent Pushing® (EFP®) method is the spectral multiplexing technique developed for improving the duty cycle of the HR-TOFMS. We report on the implementation of the EFP in HR-TOFMS with a Folded Flight Path® mass analyzer coupled with gas chromatography (GC) and two-dimensional comprehensive GC (GCxGC) for analysis of complex mixtures. This approach is expected to benefit the results of analysis of complex samples by improving limits of detection and mass spectra quality.