分散固相法与气相色谱-质谱法相结合测定自来水中的土腥味物质  

Determination of Earthy-musty Odorants in Tap Water by Gas Chro⁃matography-Mass Spectrometry with Dispersion Solid-phase

作　　者：田良良[1] 曲欣 方长玲 黄冬梅[3] 黄宣运[3] 汤云瑜 史永富[1] TIAN Liang-liang;QU Xin;FANG Chang-ling;HUANG Dong-mei;HUANG Xuan-yun;TANG Yun-yu;SHI Yong-fu(Key Laboratory of Oceanic and Polar Fisheries,Ministry of Agriculture and Rural Affairs,East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090,China;Qingdao Municipal Center for Disease Control and Prevention,Qingdao 266033,China;Key Laboratory of East China Sea Fishery Resources Exploitation,Ministry of Agriculture and Rural Affairs,East China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences,Shanghai 200090,China)

机构地区：[1]中国水产科学研究院东海水产研究所农业农村部远洋与极地渔业创新重点实验室,上海200090 [2]青岛市疾病预防控制中心,山东青岛266033 [3]中国水产科学研究院东海水产研究所农业农村部东海渔业资源开发利用重点实验室,上海200090

出　　处：《分析测试学报》2023年第7期882-887,共6页Journal of Instrumental Analysis

基　　金：中国水产科学研究院东海水产研究所中央级公益性科研院所基本科研业务费专项资金项目(2014T14);养殖暗纹东方鲀的品质调控技术研究与应用示范(2022-02-08-00-12-F01108)。

摘　　要：建立了正己烷提取、分散固相浓缩、气相色谱-质谱(GC-MS)测定自来水中土腥味物质土臭素(GSM)和2-甲基异冰片(2-MIB)的方法。通过对提取剂体积、分散固相时间、洗脱剂比例的优化,确定了最佳实验条件,即15 mL正己烷进行液液萃取,0.5 g硅胶分散固相吸附7 min,1 mL正己烷-乙酸乙酯(1∶1,体积比)进行洗脱。采用优化的GC-MS色谱条件,在选择离子监测(SIM)模式下进行测定,内标法定量。结果显示,GSM和2-MIB在0.5~500 ng/mL范围内呈良好线性关系,相关系数(r^(2))均大于0.999,检出限分别为0.8、0.4 ng/L,定量下限分别为2.5、1.5 ng/L。以自来水为空白基质,在4、8、20、80、400 ng/L加标水平下,GSM和2-MIB的平均回收率为72.7%~114%,相对标准偏差(RSD)为1.1%~7.8%。该方法操作简便,定量准确,适用于自来水中GSM和2-MIB的测定。A gas chromatography-mass spectrometry(GC-MS)with dispersive solid-phase extrac⁃tion was developed for the analysis of earthy-musty odorants,including geosmin(GSM)and 2-methyl⁃isoborneol(2-MIB)in tap water.n-hexane liquid-liquid extraction(LLE)combined with silica disper⁃sion solid-phase(DSP)was used to isolate the analytes in tap water.The pretreatment conditions in⁃cluding the volume of extractant,time of DSP and eluent ratio were optimized.The optimal experimen⁃tal conditions were as follows:the samples were extracted with 15 mL n-hexane,then the targets in ex⁃tract solution were absorbed with 0.5 g silica for 7 min,and finally,1 mL n-hexane/ethyl acetate(1∶1,by volume)was used to elute the compounds.The chromatographic conditions for detection of GSM and 2-MIB were optimized,then the supernatant was determined by GC-MS in selected ion monitoring(SIM)mode,and quantified by the internal standard method.The results showed that there were good linearities for GSM and 2-MIB in the range of 0.5-500 ng/mL,with correlation coefficients(r^(2))great⁃er than 0.999.The limits of detection(LODs)for GSM and 2-MIB were 0.8 ng/L and 0.4 ng/L,respectively,while the limits of quantitation(LOQs)for GSM and 2-MIB were 2.5 ng/L and 1.5 ng/L,respectively.The average recoveries for GSM and 2-MIB in tap water,at five spiked levels of 4,8,20,80,400 ng/L ranged from 72.7%to 114%,with relative standard deviations(RSDs)of 1.1%-7.8%.The method is simple in operation and accurate in quantification,and it is suitable for the de⁃termination of GSM and 2-MIB in tap water.

关 键 词：土臭素(GSM) 2-甲基异冰片(2-MIB) 正己烷 硅胶 气相色谱-质谱法(GC-MS) 自来水 

分 类 号：O657.63[理学—分析化学] O741.6[理学—化学]