超高效液相色谱串联质谱法测定大气颗粒物中脱水单糖

Determination of Monosaccharide Anhydrides in Atmospheric Particles by Ultrasonic Extraction Coupled with Chromatography-Tandem Ultra High Performance Liquid Mass Spectrometry

采用超声萃取与超高效液相色谱-串联质谱联用，建立了测定大气颗粒物中左旋葡聚糖及其异构体——甘露聚糖及半乳聚糖的方法。颗粒物样品用甲醇超声萃取，浓缩后使用超高效液相色谱-串联质谱分析。采用电喷雾电离方式，对色谱及质谱条件进行优化，对超声萃取条件进行筛选，并进行实际样品测定。在优化的多反应监测模式下，方法回收率在80．5％-92．2％之间，检出限左旋葡聚糖为2．0ng／mL，甘露聚糖及半乳聚糖为3．0ng／mL。相对标准偏差15％以下。相比气相色谱-质谱联用分析左旋葡聚糖及异构体的方法，本方法不用衍生，节省了人力、物力，更快速、经济、灵敏，实际样品的测试证明本方法可以满足大气颗粒物中此类化合物的定量分析要求。

In order to do source appointment of atmospheric particles, an analytical method was developed for determination of monosaccharide anhydrides （levoglucosan and its 2 isomers） in atmospheric particles by ultrasonic extraction coupled with ultra performance liquid chromatography -tandem mass spectrometry （UPLC-MS /MS）. After extraction by methanol and enrichment, isomers were separated on a BEH Amide C18 column （100mm×2. l mm, 1.7μm）, with acetonitrile and water served as mobile phase in gradient elution, then determined by UPLC-MS/MS using electrospray negative ionization （ESI） and multiple reaction monitoring （MRM）. Parameters of chromatography and mass spectrometry, as well as conditions of ultrasonic extraction were optimized through experiments. The developed method provided good linearities（r^2〉0.99） and recoveries（80.5%-92.2%） for 3 isomers. Low detection limit for levoglucosanis 2.0ng/mL, mannosan and galactosanis 3.0ng/mL respectively, RSD is less them 15% （n=6）. Comparing with GC/MS, this method is more rapid, sensitive and economical because derivation is eliminated,itsaves human and material resources. Samples of atmospheric particles are detected using this method,it can meet the requirements of quantitative analysis of monosaccharide anhydrides in atmosphere.