Ion Mobility Spectrometer Optimized Orthogonal Experimental Design

Ion mobility spectrometry (IMS) is a new chemical analysis and trace amount detecting technology which was presented in the 1960's. It had been applied to analysis and detecting on-the-spot in the 1980's. In order to analyze materials, it gives an index to various chemical materials by means of the resolution of gaseous ions. Compared with other chemical analysis technologies, such as MS and GC, IMS is similar to them in principle, but it also has its distinctive virtues. Ion mobility spectrometer can work at atmospheric pressure and room temperature. It has advantages of small volume, high sensitivity, broad applicability, low power consumption and high speed.The paper mainly introduces the ion mobility spectrometer that was designed independently in our laboratory, which adopted krypton fluoride excimer laser as ionization source. The paper gives an introduction to the principle and system configuration of a laser ionization source for ion mobility spectrometer and then describes the results of preparatory optimization and orthogonal experiment optimization.The main content and achievements of this paper include three items as follows:1. The preparatory optimization designs were carried out by means of detecting xylene. The influences of electric field intensity, mobility tube length, sample flux, mobility gas flux, and temperature on signal intensity were summarized. At the same time, the operation ranges were confirmed. As long as the appropriate voltage, temperature, mobility tube length, and sample flux were chosen, ion mobility spectrometer can receive better signals and higher exploration sensitivity.2. The orthogonal design was carried out on the progress of ion mobility spectrometer using orthogonal experiment design method. The experiment was carried out according to the ways and means that had been designed. The orthogonal experiment design method was contrived using Statistical Product and Service Solutions. According to the main factors that influence the signal intensity, the optimum design of the optimization of ion mobility spectrometer was achieved.Some important conclusions were received by optimizing the instruments. These conclusions have particular direction significance to the experiments which will be carried out in the future.