ABSTRACT
The goal of this chapter is to introduce the reader to the basic concepts of FAIMS, and to familiarize the reader with the diversity and scope of this gas-phase ion separation technique. Section 5.1 will review briey the basic principles of ion mobility spectrometry (IMS) that are necessary for introducing FAIMS, including a discussion of ion properties under the inuence of high electric elds. In addition, a historical timeline for the development of FAIMS will be given. Section 5.2 will introduce a simplied FAIMS system that will serve to illustrate the fundamental concepts and terminology. The discussion in this chapter will progress through various examples of increasing complexity. Section 5.3 will expand on the role of two critical variables in FAIMS separations: the bath gas and the gas number density. Section 5.4 will examine more closely the diversity of hardware used in FAIMS, exploring different variants of the electrode set and the waveform generator, ending with a brief discussion of some of the commercially available FAIMS devices. Section 5.5 will present a wide range of different applications in which FAIMS has been used in conjunction with mass spectrometry. The chapter will conclude (Section 5.6) with the author’s view on the future direction of FAIMS.
