固相萃取-超高效液相色谱-串联质谱法测定葡萄酒中赭曲霉毒素A和赭曲霉毒素α

目的建立使用同位素内标法定量测定葡萄酒中赭曲霉毒素A和赭曲霉毒素α的超高效液相色谱-串联质谱法。方法葡萄酒样品经5%氨水调至pH 9.0后,用MAX固相萃取小柱富集。以乙腈和5 mmol/L乙酸铵溶液为流动相,采用等度洗脱方式在ACQUITY BEH C18(100 mm×2.1 mm,1.7μm)色谱柱上分离,以电喷雾正离子模式进行质谱检测,内标法定量。结果赭曲霉毒素A和赭曲霉毒素α在1.0~50.0μg/L范围内,线性关系良好,r分别为0.9996和0.9993,方法的检出限均为0.10μg/kg,定量限均为0.35μg/kg。加标浓度0.35、2.00和10.00μg/kg时,方法的平均回收率为88.6%~108.0%,相对标准偏差为2.1%~9.2%(n=6)。结论该方法前处理简单、灵敏度高、准确、可靠,适用于葡萄酒中赭曲霉毒素A和赭曲霉毒素α的测定。

Determination of ochratoxin A and ochratoxin alpha in wine by ultra-performance liquid chromatography tandem mass spectrometry

OBJECTIVE To establish a method for determination of ochratoxin A and ochratoxin alpha in wine by ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) based on isotopic internal standard method. METHODS The wine sample was adjusted to pH 9.0 by 5% ammonia and concentrated by a MAX solid phase extraction cartridge. The UPLC separation was performed on a ACQUITY BEH C18 column(100 mm×2.1 mm,1.7 μm)with a isocratic elution program of acetonitrile and 5 mmol/L ammonium acetate as the mobile phase. Electrospray ionization was applied and operated in the positive ion mode. The concentration of wine was quantified by isotope internal standard. RESULTS The calibration curves were linear in the concentration range of 1.0-50.0 μg/L,the coefficients of correlation were 0.9996 and 0.9993, respectively. The limits of detection(LODs) of both were 0.10 μg/kg, and the limits of quantitative were 0.35 μg/kg. The average recoveries at the spiked levels of 0.35, 2.00 and 10.00 mg/kg were 88.6%-108.0%, and the relative standard deviations(RSDs) were 2.1%-9.2%, respectively. CONCLUSION This method is simple, sensitive, accurate and reliable, which is suitable for the determination of ochratoxin A and ochratoxin alpha in wine.