PM2.5和PM10中6种砷形态的高效液相色谱-电感耦合等离子体质谱测定法

Determination of six arsenic species in PM_(2.5) and PM_(10) high performance liquid chromatography with inductively coupled plasma mass spectrometry

目的建立大气中细颗粒物(fine particulate matter,PM_(2.5))和可吸入颗粒物(inhalable particles,PM_(10))中6种砷形态的高效液相色谱-电感耦合等离子体质谱(high performance liquid chromatography-inductively coupled plasma mass spectrometry,HPLC-ICP-MS)测定法。方法PM_(2.5)和PM_(10)滤膜经乙酸和抗坏血酸的混合溶液涡旋振荡提取,采用HAMILTON PRP-X100色谱柱(250 mm×4.1 mm,10μm),以50 mmol/L碳酸铵溶液(pH=8.30)为流动相进行梯度洗脱,流速为0.9 mL/min,用HPLC-ICP-MS进行检测。结果在1.0~50.0 ng/mL的浓度范围内,6种砷形态均呈较好的线性关系,相关系数r≥0.9990。PM_(2.5)和PM_(10)中砷胆碱(arsenocholine,AsC)、砷甜菜碱(arsenobetaine,AsB)、三价砷[arsenious acid,As(Ⅲ)]、二甲基砷(dimethylarsinic acid,DMA)、一甲基砷(monomethylarsonic acid,MMA)和五价砷[arsenic acid,As(Ⅴ)]的方法检出限(3S/N)分别为0.025、0.020、0.044、0.016、0.014和0.009 ng/m^(3)。PM_(2.5)和PM_(10)中6种砷形态化合物的回收率范围分别为77.8%~103.4%、76.9%~108.1%,相对标准偏差(relative standard deviation,RSD)范围分别为1.6%~6.1%、2.5%~6.1%。结论该方法简便、快速、灵敏度高,适用于大批量PM_(2.5)和PM_(10)中6种砷形态的检测。

Objective To establish a method for the determination of six arsenic species in fine particulate matter(PM_(2.5))and inhalable particles(PM_(10))by high performance liquid chromatography with inductively coupled plasma mass spectrometry(HPLC-ICP-MS).Methods PM_(2.5) and PM_(10) filter membranes were extracted with vibrated by a mixture solution of acetic acid and ascoibic acid.The six arsenic species were separated by HAMILTON PRP-X100 chromatographic column(250 mm×4.1 mm,10μm)with 50 mmol/L ammonium corbonate solution(pH=8.30)as mobile phase for gradient elution at a flow rate of 0.9 mL/min,then determined by HPLC-ICP-MS.Results Six arsenic species in the range of 1.0-50.0 ng/mL showed a good linearity,with the correlation coefficients r≥0.9990.The limits of detection(3S/N)of arsenocholine(AsC),arsenobetaine(AsB),arsenious acid[As(Ⅲ)],dimethylarsinic acid(DMA),monomethylarsonic acid(MMA)and arsenic acid[As(Ⅴ)]in PM_(2.5) and PM_(10) were 0.025,0.020,0.044,0.016,0.014and 0.009 ng/m^(3),respectively.The recoveries of six arsenic species in PM_(2.5) and PM_(10) were 77.8%-103.4%and 76.9%-108.1%respectively,and the relative standard deviations(RSD)were 1.6%-6.1%and 2.5%-6.1%respectively.Conclusion This method is proved to be simple,rapid and sensitive,and it is suitable for the determination of six arsenic species in a large scale of samples of PM_(2.5) and PM_(10).