The ion-guiding UQ and the mass-resolving DQ have been repurposed from commercial mass spectrometers (Thermo Scientific). UQ has 250 mm long hyperbolic rods with a 6 mm field radius and DQ is a part of the linear quadrupole trap assembly, which has 60 mm long hyperbolic rods and a 4.75 mm field radius. DQ is enclosed and has entrance and exit electrodes. Its inner volume is filled at a flow rate of 1 sccm with lab air, which results in a pressure of 10 -3 -10 -2 hPa in the enclosure. Both quadrupoles are powered by dedicated voltage sources (JanasCard, Czechia) that can float at a potential up to 1 kV. The sources provide harmonic voltages in the 0.5-100 kHz range with constant amplitude (100 and 200 V) and variable DC component (0 to ±35 V). While UQ was operated in the ion guide mode with 0 DC voltage, DQ was used in either resolving (33.4 V of the DC component) or non-resolving (0V for the DC component) mode of operation.