高效液相色谱-串联质谱法测定淡水养殖池塘水体及鱼虾体内的藻毒素

采用高效液相色谱-串联质谱法测定了淡水养殖池塘水体及鱼虾体内藻毒素MC-LR和MC-RR。水样经微孔滤膜过滤后,通过固相萃取柱富集净化。鱼、虾冻干后粉碎,以甲醇水溶液提取,提取液经固相萃取柱富集净化。采用UPLC BEH C18色谱柱(100×2.1mm,3.5μm),以0.1%甲酸水溶液和含0.1%甲酸乙腈溶液为流动相,质谱采用选择离子监测模式测量。结果表明,藻毒素的质量浓度在0.5~500μg·L~(-1)范围内时,峰面积与样品浓度呈良好线性关系。MC-LR和MC-RR的方法检出限分别为0.05μg·L~(-1)和0.08μg·L~(-1)。藻毒素在空白水样中的加标回收率为88.5%~98.5%,相对标准偏差为5.2%~8.3%;在鱼、虾组织中的加标回收率为63.8%~85.2%,相对标准偏差为6.7%~9.8%。实际测得某养殖池塘水中存在藻毒素污染,且部分水产品中检测到了MC-LR和MC-RR。

Determination of Microcystins in Fresh Aquaculture Water and Aquatic Products by High Performance Liquid Chromatography-Tandem Mass Spectrometry

The microcystins(MC-LR and MC-RR) in fresh aquaculture water and aquatic products were determined by high performance liquid chromatography-tandem mass spectrometry.The water samples were enriched and purified by solid phase extraction after microporous membrane filtration.Fish and shrimp were extracted with methanol water solution after freeze-drying and pulverization.A mixture of 0.1％ formic acid aqueous solution and 0.1％ formic acid acetonitrile solution were used as mobile phase and C18 column as stationary phase.The selected ion monitoring mode was used for specific measurement of MC-LR and MC-RR.The mass concentration and peak area showed a good linear relationship in the range of 0.5-500 μg·L-1 for MC-LR and MC-RR,respectively.The detection limit (S/N=3) was 0.05 μg·L-1 for MC-LR and 0.08 μg·L-1 for MC-RR,respectively.The recoveries for spiked water samples were in the range of 88.5％-98.5％ with the RSD between 5.2％ and 8.3％.The recoveries for spiked tissues of fish and shrimp samples were in the range of 63.8％-85.2％ with the RSD between 6.7 ％ and 9.8％.Monitoring results showed that the microcystins existed in aquaculture pond water and were detected in some of the aquatic products.