液相色谱-串联质谱法同时测定贝类中大田软海绵酸、鳍藻毒素、蛤毒素和虾夷扇贝毒素

建立了同时测定贝类中大田软海绵酸(okadaic acid, OA)及其衍生物鳍藻毒素(dinophysistoxin-1, DTX-1)、蛤毒素(pectenotoxin-2, PTX-2)和虾夷扇贝毒素(yessotoxin, YTX)的液相色谱-串联质谱分析方法。样品经甲醇提取,固相萃取柱净化,C18色谱柱分离,经含甲酸和甲酸铵的乙腈-水溶液为流动相梯度洗脱,选择反应监测(SRM)模式检测,正、负离子切换扫描,基质标准校正,外标法定量。结果表明,OA、DTX-1和YTX的线性范围为2.0～200.0 μg/L,定量限(以信噪比(S/N)≥10计)为1.0 μg/kg; PTX-2的线性范围为1.0～100.0 μg/L,定量限为0.5 μg/kg;几种化合物的添加平均回收率为83.1%～105.7%,相对标准偏差(RSD)为3.16%～9.29%。成功应用本法对黄海灵山湾海域采集的贝类样品进行了分析,发现部分样品中含有大田软海绵酸、鳍藻毒素、蛤毒素和虾夷扇贝毒素。

Simultaneous determination of okadaic acid, dinophysistoxin, pectenotoxin and yessotoxin in shellfish by liquid chromatography-tandem mass spectrometry

A method for the simultaneous determination of okadaic acid (OA) and its derivatives dinophysistoxin-1 (DTX-1), pectenotoxin-2 (PTX-2) and yesstoxin (YTX) in shellfish using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. After being extracted with methanol, the extract was cleaned-up by solid phase extraction of a Strata-X cartridge. The separation of the 4 toxins were performed on a XTerra MS C18 column (100 mm x 2.1 mm, 3.5 microm) using gradient elution of acetonitrile and water both containing ammonium formate and formic acid as eluent modifiers. The qualitative and quantitative analysis were carried out by electrospray ionization (ESI) mass spectrometry in selective reaction monitoring (SRM) mode. The OA, DTX-1 and YTX were analyzed in negative ion mode, while PTX-2 in positive ion mode. The matrix-matched external standard calibration curves were used for the quantitative analysis. The calibration curves were linear in the range of 2.0 - 200.0 microg/L for OA, DTX-1 and YTX, 1.0 - 100.0 microg/L for PTX-2, with the quantification limits of 1.0 microg/kg and 0.5 microg/kg, respectively. The average recoveries for the toxins were between 83. 1% and 105.7% with the relative standard deviations (RSD) of 3.16% - 9.29%. The proposed method is sensitive, effective and simple. It was applicable for the determination and confirmation of OA, DTX-1, PTX-2 and YTX in shellfish products. The OA, DTX-1, PTX-2 and YTX in some shellfish samples collected from Yellow Sea were found by the method.