| Autor: |
Conant CR; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Attah IK; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Garimella SVB; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Nagy G; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Bilbao A; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Smith RD; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States., Ibrahim YM; Biological Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States. |
| Abstrakt: |
Structures for lossless ion manipulations (SLIM) have recently enabled a powerful implementation of traveling wave ion mobility spectrometry (TWIMS) for ultrahigh resolution separations; however, experimental parameters have not been optimized, and potential significant gains may be feasible. Most TWIMS separations have utilized square-shaped waveforms applied by time-dependent voltage stepping across repeating sets of electrodes, but alternative waveforms may provide further improvements to resolution. Here, we characterize five waveforms (including square and sine) in terms of their transmission efficiency, IMS resolution, and resolving power, and explore the effects of TW amplitude and speed on the performance of each. We found, consistent with previous work, separations were generally improved with higher TW amplitudes, moderately improved by lower speeds (limited by ion "surfing" with the waves), and found decreases in signal intensity at the extremes of operating conditions. The triangle and asymmetric "ramp forward" shaped profiles were found to provide modestly greater resolution and resolving power, an observation we tentatively attribute to their relatively uniform fields and minimal low-field regions. |
