A Comparison of Travelling Wave and Drift Tube Ion Mobility Separations
This poster was presented at ASMS 2006. Ion Mobility TWIMS displays the same general trends of charge separation and mass correlation seen in drift tube IMS. A generalization of the collision cross section versus drift time equation allows for an accurate calibration of the TWIMS device resulting in calculated collision cross sections within +/- 3.5% (2SD). The coefficients in the generalised equation needs further investigation both in terms of reproducibility over a range of TWIMS conditions and in terms of origin. A simple periodic voltage waveform together with a drag model for ion motion gives a reasonable prediction of drift time through the TWIMS device.