氨是水体主要的污染物之一,其含量是水质评估的重要参数。本研究采用真空紫外光离子源-高场不对称波形离子迁移谱(Ultraviolet photoionization high field asymmetric waveform ion mobility spectrometry,UVFAIMS)技术,发展一种的水中氨含量的现场快速检测方法。通过对比标准氨样品和水中微量氨UV-FAIMS谱图峰的特征补偿电压(Compensation voltage,CV)值,确定了水中HN+4的特征离子峰位置;研究了不同分离电压(Dispersion voltages,DV)下HN4^+谱图峰位置的关系,获得了HN4^+的特征识别系数α2和α4分别为2.21×10^-5Td^-2和-1.45323×10^-9Td^-4;通过不同浓度样品的信号响应,研究了UV-FAIMS对水中氨的检出限,在信噪比为3的情况下达到了9.2μg/L。本研究为水中氨现场检测提供了一种快速、无需前处理的技术手段。
A novel on-site rapid detection method for ammonia detection in water was developed by using ultraviolet photoionization high field-asymmetric waveform ion mobility spectrometry(UV-FAIMS). The position of ammonia characteristic ion peak was acquired by the comparison between the characteristic compensation voltage(CV)in standard ammonia sample and trace amount ammonia in water. The relation between the positions of ammonia characteristic ion peaks under different dispersion voltages(DV) was studied. The values of α2,α4were 2. 21 × 10^-5Td^-2and-1. 45323 × 10^-9Td^-4,respectively. The different concentrations of ammonia in water was measured with a limit of detection(LOD)of 9. 2 μg / L(S / N = 3).This study provided a rapid,non-pretreatment means for the detection of ammonia in water matrices.