高场非对称波形离子迁移谱检测分析二氧化硫

Detection and analysis of sulfur dioxide by high-field asymmetric waveform ion mobility spectrometry

采用高场非对称波形离子迁移谱对二氧化硫进行分析检测,建立了动态气体浓度配气系统,考察了0. 025×10-6~7. 5×10-6范围内的FAIMS响应峰值、信噪比等信号参数,分析得出了二氧化硫在负模式下电离生成了一种产物离子(SO2)O2-(H2O)n-1,且峰值随浓度增大先增大后逐渐饱和,其中分离电场为45%时SO2产物离子峰峰值与浓度呈一定线性,线性方程为y=0. 793 3x+0. 059 2,线性回归率为0. 971,FAIMS对二氧化硫的检测下限为3. 5×10-9,证实了FAIMS灵敏度高的特性,并且可以对物质进行定量和半定量检测,对危险化学品事故应急侦检具有指导意义。

High field asymmetric waveform ion mobility spectrometry( FAIMS) is used to analyze and detect sulfur dioxide,and a dynamic gas concentration distribution system is established. Signal parameters such as FAIMS response peak values and signal-to-noise ratio in the range of 0. 025 × 10-6-7. 5 × 10-6 are investigated. It is analyzed that in the negative mode,sulfur dioxide ionizes to form a product ion,namely( SO2)O2-( H2O)n-1. Peak value of product ion increases firstly and saturates then as the concentration of sulfur dioxide increases,where the product ion peak value of SO2 has a linear relationship with the concentration at DF = 45%. The linear equation is y = 0. 793 3 x + 0. 059 2,with a linear regression rate of 0. 971.The lower limit of detection for sulfur dioxide by FAIMS is 3. 5×10-9.It is confirmed that FAIMS exhibits high sensitivity,and can quantitatively and semi-quantitatively detect substances,which has important guiding significance for emergency detection of dangerous chemical accidents.