| 摘要 |
A method of mass spectrometry is disclosed comprising separating a first population of ions according to their ion mobility and selectively attenuating ions in the firstpopulation of ions in one or more ion mobility and/or drift time ranges so as to form a second population of ions, before then separating the second population of ions according to their ion mobility. The step of selectively attenuating ions comprises applying a varying, increasing or decreasing attenuation factor to ions in different ion mobility and/or drift time ranges. Preferably, attenuated and non-attenuated ions exiting an attenuation device 4 are accumulated in an ion trap 5, at which point any mobility separation provided by the first IMS 3 is lost. The invention is aimed at reducing space charge and saturation effects in ion mobility spectrometry experiments. |
