柱前还原衍生-顶空气相色谱法测定冰冻鱼和虾中甲醛  

Determination of formaldehyde in frozen fishes and shrimps by headspace gas chromatography with pre-column reducing derivatization

作　　者：赵丹莹[1] 温雅[1] 郭蒙京[1] 王玮[1] 李堃[1] 高洋洋[1] ZHAO Dan-ying;WEN Ya;GUO Meng-jing;WANG Wei;LI Kun;GAO Yang-yang(Physical and Chemical Laboratory,Xicheng Distict Center for Disease Control and Prevention,Beijing,100120,China)

机构地区：[1]北京市西城区疾病预防控制中心理化检验科

出　　处：《中国卫生检验杂志》2019年第9期1043-1045,1059,共4页Chinese Journal of Health Laboratory Technology

基　　金：北京市西城区委组织部西城区优秀人才课题(2016-0049)

摘　　要：目的建立柱前还原衍生-顶空气相色谱法测定冰冻鱼和虾中甲醛的新方法,解决目前食品中甲醛测定方法样品前处理复杂、稳定性差的问题。方法取一定量匀浆后海鲜样品,加入0.10mol/L硼氢化钠-1.0mol/L氢氧化钠(1∶10,V/V)还原剂,使样品中甲醛还原为甲醇,离心后取上清液于顶空瓶中,90℃下以顶空进样器加热30min后进样,经DB-WAX色谱柱(60m×0.32mm,0.5μm)分离、FID检测,外标法定量。结果还原液对浓度<15.6mg/L的甲醛标准溶液还原效率可达100%,且无基质干扰。在0.4mg/L^15.6mg/L浓度内,相关系数>0.9987,加标回收率为87.3%~107.3%,方法检出限为0.4mg/kg,相对标准偏差<8.1%。本法对鱼、虾样品的测定结果与国家标准方法SC/T3025—2006测定结果一致。结论本法操作简便,准确、稳定,适用于冰冻鱼和虾样品中甲醛的测定。Objective To establish a new method for determining formaldehyde in frozen fish and shrimp by headspace gas chromatography with pre-column reducing derivatization,which can solve the problem of complex pretreatment and poor stability when determining formaldehyde in food. Methods Reducing agent,0. 1 mol /L NaBH4-1. 0 mol /L NaOH ( 10∶1,V/V), was added in a certain amount of homogenized seafood samples. Formaldehyde in the sample can be reduced to methanol,which can be determined by headspace gas chromatography with FID detector after headspace ( 90 ℃,30 min) and centrifuge treatment. It was separated by DB -WAX column ( 60 m × 0. 32 mm,0. 5 μm),detected by FID,and quantified by external standard method. Results The reducing solution had a reduction efficiency of 100% for formaldehyde solution with a concentration of less than 15. 6 mg /L and no matrix interference. In 0. 4 mg /L-15. 6 mg /L,the correlation coefficient was greater than 0. 998,and the recoveries were within 87. 3%-107. 3%. The detection limit was 0. 4 mg /kg,and the relative standard deviation was less than 8. 1%. The test results of fish and shrimp samples in this method were consistent with the results of the national standard method SC/T 3025-2006. Conclusion This method can determine formaldehyde concentration simply, rapidly,accurately and steadily. It is suitable for determining formaldehyde in frozen fish and shrimp.

关 键 词：甲醛 甲醇 氧化-还原反应 顶空气相色谱 

分 类 号：O657.71[理学—分析化学]