固相微萃取/气相色谱/燃烧-同位素比值质谱技术测定水体中微量苯系物单体碳同位素方法研究  

Research on the Method for Determining Compound Specific Carbon Isotopes of Trace Benzenes in Water by Solid Phase Microextraction/Gas Chromatography/Combustion-Isotope Ratio Mass Spectrometry

作　　者：漆艳 尹希杰 李玉红 林锡煌 QI Yan;YIN Xi-jie;LI Yu-hong;LIN Xi-huang(Information and Testing Support Center,Third Institute of Oceanography,Ministry of Natural Resources,Xiamen 361005,China;Zhoushan Field Scientific Observation and Research Station for Marine Geo-hazards,China Geological Survey,Qingdao 266237,China)

机构地区：[1]自然资源部第三海洋研究所分析测试中心,福建厦门361005 [2]中国地质调查局舟山海洋地质灾害野外科学观测研究站,山东青岛266237

出　　处：《分析测试学报》2024年第9期1474-1480,共7页Journal of Instrumental Analysis

基　　金：中国地质调查局舟山海洋地质灾害野外科学观测研究站开放基金资助项目(ZSORS-22-10)。

摘　　要：该文建立了固相微萃取/气相色谱/燃烧-同位素比值质谱(SPME/GC/C-IRMS)技术测定水体中7种苯系物碳同位素(δ^(13)C)的方法。实验结果表明,萃取温度30℃,萃取时间60 min条件下萃取效果最佳,萃取温度(30~60℃)和萃取时间(15~60 min)对顶空萃取(HS-SPME)过程中的碳同位素分馏无影响。最佳萃取条件下,利用HS-SPME和直接萃取(D-SPME)方法分别测试7种苯系物的δ^(13)C值,标准偏差分别为0.08‰~0.45‰和0.05‰~0.39‰,测试误差分别为-0.16‰~0.33‰和-0.41‰~0.46‰,两种SPME方式在萃取过程中均未发生明显碳同位素分馏,HS-SPME的灵敏度比D-SPME方法高1~2个数量级。通过移动平均值算法计算苯、间/对二甲苯、异丙苯的检出限为1μg/L,甲苯、乙苯、邻二甲苯、苯乙烯的检出限为2μg/L。测得江苏某废弃农药场地下水中7种苯系物δ^(13)C值的标准偏差为0.01‰~0.43‰。该方法样品前处理简单、灵敏度高、准确性好,适用于水体中痕量苯系物单体碳同位素的检测。This study introduces a solid phase microextraction/gas chromatography/combustion-iso⁃tope ratio mass spectrometry(SPME/GC/C-IRMS)technology for analyzing the carbon isotopes of sev⁃en benzene series compounds in water.The pretreatment conditions for headspace solid phase micro⁃extraction(HS-SPME)were optimized.The results demonstrated that the extraction efficiency reached its maximum at an extraction temperature of 30℃and an extraction time of 60 minutes.Vari⁃ations in extraction temperature(30-60℃)and extraction time(15-60 min)did not cause carbon iso⁃tope fractionation during HS-SPME.Under the optimized extraction conditions,both HS-SPME and D-SPME methods were employed to measure theδ^(13)C values of the seven benzene series compounds.The standard deviations ranged from 0.08‰-0.45‰and 0.05‰-0.39‰,and the test error varied from-0.16‰-0.33‰and-0.41‰-0.46‰,respectively.No obvious carbon isotope fractionation occurred during the extraction process in both SPME methods,and the sensitivity of the HS-SPME method is 1-2 orders of magnitude higher than the D-SPME method.Utilizing the moving average al⁃gorithm,the detection limits for benzene,m-/p-xylene,and isopropylbenzene were determined to be 1μg/L,while for toluene,ethylbenzene,o-xylene and styrene,the detection limits were 2μg/L.This method was applied to analyze groundwater from an abandoned pesticide factory in Jiangsu,yield⁃ingδ^(13)C values for the seven benzene series compounds with good repeatability(standard deviation:0.01%-0.43‰).This method can be applied to detect the carbon isotope for trace benzene series com⁃pounds in water,because of the simple pretreatment procedure,high sensitivity and good accuracy.

关 键 词：苯系物 固相微萃取 气相色谱/燃烧-同位素质谱 单体碳稳定同位素分析 水体 

分 类 号：O657.63[理学—分析化学] X132[理学—化学]