固相萃取-液相色谱-串联质谱法测定贝类中的脂溶性贝类毒素

Determination of lipophilic marine toxins in shellfish by high performance liquid chromatography-tandem mass spectrometry with solid phase extraction

目的建立了测定贝类中大田软海绵酸(OA)、鳍藻毒素(DTX1、DTX2)、紫贻贝毒素(YTX)、原多甲藻酸贝毒素(AZA1)、螺环内酯毒素(SPX1)6种脂溶性贝类毒素的固相萃取-高效液相色谱-串联质谱方法。方法匀浆贝类组织,用80%甲醇提取,Strata^(TM)-X固相萃取小柱净化,0.3%氨水甲醇溶液洗脱,离心超滤管离心纯化。采用XTerra MS C_(18)柱(150 mm×2.1 mm,35μm)分离,以含6.7 mmol/L氨水的90%乙腈-水溶液为流动相进行梯度洗脱,选择多反应监测模式检测,正、负离子切换扫描,基质标准校正外标法定量。结果 6种脂溶性贝类毒素的定量限为0.2~1.0μg/kg,在相应浓度范围内线性良好,相关系数均>0.995;低、中、高3个添加水平的平均加标回收率在78.8%~116%之间;相对标准偏差(RSD)为3.8%~14.5%。应用建立的方法对多份贝类样品进行分析,均未检出目标组分。结论方法选择性、灵敏性和准确度高,适用于贝类产品中脂溶性贝类毒素的确证及定量分析。

Objective A solid-phase extraction coupled to high performance liquid chromatography-tandem mass spectrometry （LC-MS/MS） was developed for determination of six lipophilic marine toxins, including OA, DTX2, YTX, DTX1, AZA1 and SPX1 in shellfish. Methods Homogenised tissues were extracted twice with 80% methanol in water, and resulting extracts were cleaned-upon StrataWM-x solid phase extraction column and eluted with MeOH solutions containing 0.3% NH4OH, followed by filtering through a ultra-fiher centrifuge tube. The target components were separated and gradient eluted on a XTerra MS Cls column using mobile phases of MeCN/water and water, both phase containing 6.7mmol/L NH4OH, and simultaneously quantified by switching alternatively between positive ions and negative ions under multiple reactions monitoring mode. The matrix-matched external standard calibration were carried out for the quantitative analysis. Results The limits of quantification ranged from 0.2 to 1.0 μg/kg for six marine lipophilic toxins. The calibration curves were linear in the respective concentration ranges, with the correlation coefficients 〉 0. 995. The average recoveries for toxins at three concentration levels were 78.8% -116% , and their relative standard deviation varied between 3.8% and 14.5%. The method was applied to analyze several shellfish samples, but no one was positive. Conclusion The method developed was selective, sensitive and accurate, and was suitable for analysis and confirmation of marine lipophilic toxins in shellfish.