中文摘要：

人体呼出气体携带大量的生理病理信息,在临床诊断和代谢组学研究中发挥着日益重要的作用。本研究在未对样品进行预处理条件下,采用电喷雾萃取电离质谱（EESI-MS）技术直接测定呼出气体中乙腈分子。在优化的实验条件下,结合多级串联质谱,有效地获得了人体呼出气体中乙腈含量的信息。对气相乙腈的检出限为5.71 pL/L,线性范围为76.4～1910 pL/L。以两名健康志愿者呼出气体为实例,实际检测了其中乙腈的含量分别为134.49和104.40 pL/L,相对标准偏差（RSD）分别为6.3%和7.2%。结果表明,本方法灵敏度高、精密度好、分析速度快、特异性强,能够承受呼出气体中复杂基体的影响,适合于呼出气体中痕量乙腈的直接半定量检测,也可为呼出气体中其它小分子物质的检测提供新思路。

英文摘要：

Breath analysis by virtue of its potential medical research value,and as a non-invasive sample,simple sampling and continuous available is of interest for modern clinical diagnosis and metabonomics.The concentration levels of acetonitrile,an important biomarker in human exhaled gas,are correlated with human health.Herein we constructed a novel platform of extractive electrospray ionization-mass spectrometry（EESI-MS） for direct,rapid detection of acetonitrile in human breath without any sample pretreatment.Under the optimized working conditions,the quantitative information of acetonitrile in human breath was acquired effectively.For acetonitrile,a limit of detection was found to be 5.71 pL/L;the linear range was from 76.4 pL/L to 1910 pL/L.The concentration of acetonitrile in the exhaled breath of two healthy volunteers was in vivo determined to be 134.49 and 104.40 pL/L,respectively,the relative standard deviations were 6.3% and 7.2%.The results show that EESI-Ion Trap MS is a powerful analytical platform to provide high sensitivity,high precision,rapid analysis and high specificity for semi-quantitative analysis of acetonitrile in human breath,and for detection of other bio-molecules in exhaled breath potentially.