Ion Mobility Spectrometry


The technical principle of the practice of ion mobility spectrometry (IMS according to the terms in English) consists of the inspection cameras in the bypass tube, through the semipermeable membrane that has the function of selective permeability, after they are heated and vaporized at the entrance.


After ionization by the ionizing source, the different molecules form groups of molecular ions, which drift towards the detectors at different speeds under the influence of the electrical field of the shunt tube, and ultimately form current pulses in the detectors, which that allows to present the ion mobility spectroscopy, with the mobility time as its transverse axis, and the current intensity as its vertical axis.

Because the speed of mobility is based on mass, size, and electrical charge, different substances are distinguished in spectroscopy by peaks at different positions. With the development of technology, in addition to the classic ion mobility spectrometry, high electric field asymmetric ion mobility spectrometry (FAIMS) and other new technologies have been developed.

IMS-based inspection has become the most practical method for trace detection in the detection of narcotic drugs, explosives, chemical warfare agents and industrial toxic gas, etc., because IMS systems can operate under atmospheric pressure and count with high detection sensitivity, fast analysis, small size, light weight and very low power consumption.