提出了应用高效液相色谱-串联质谱法测定水产品中硝基呋喃代谢物的含量.样品中与蛋白质结合的硝基呋喃代谢物在稀盐酸中水解释出,与加入的衍生试剂2-硝基苯甲醛(2-NBA)发生衍生化反应.衍生化产物用乙酸乙酯萃取,经正己烷净化后供高效液相色谱分离及质谱测定.结果表明:萃取宜在pH 7.0左右进行,且衍生化以后的操作过程应在避光的条件下进行,以免影响测定结果.色谱分离中采用17 mmol·L-1乙酸和乙腈作流动相梯度淋洗.在串联质谱检测中采用电喷雾离子源正离子和多反应选择离子监测模式.方法的检出限(3S/N)在0.1~0.5 μg·kg-1之间.以3种不同水产品为基体分别加入4种代谢物标准(浓度为0.5 μg·kg-1)作回收试验,测得平均回收率在86%~102%之间,相对标准偏差(n=8)小于13%.

The method of HPLC-MS/MS was applied to the determination of metabolites of nitrofurans in aquatic products.The protein-bound metabolites were liberated from the sample by hydrolysis in dil.HCl medium and derivatized simultaneously with 2-nitrobenzaldehyde.The derivatized products were extracted with ethyl acetate and purified with n-hexane,which was then used for HPLC-MS/MS determination.It was proved that the extraction should be carried out in the medium having its pH value around 7.0 and the operation (including the purification) should be kept away from sunshine.A mixture containing 17 mmol·L-1 HOAc and acetonitrile was used as mobile phase in HPLC separation and the ESI+ with MRM was used in MS/MS determination.Detection limits (3S/N) found were in the range of 0.1-0.5 μg·kg-1.Standards of 4 metabolites with concentration of 0.5 μg·kg-1 were added to 3 different kinds of aquatic products and tested for the recovery,values of recovery obtained were in the range from 86% to 102%.Values of RSD′s (n=8) found were less than 13%.