同位素内标高效液相色谱-串联质谱法测定粮食及其制品中赭曲霉毒素A、B和C

Determination of Ochratoxin A,B and C in Cereals and Its Products by High-performance Liquid Chromatography-tandem Mass Spectrometry Using an Isotope Internal Standard

建立一种同位素内标高效液相色谱-串联质谱法同时测定粮食及其制品中赭曲霉毒素A、B和C的方法。样品用乙腈-水(84∶16,V/V)提取,振荡离心后取上清液过赭曲霉毒素免疫亲和柱富集净化,经Waters ACQUITY BEH C18(50 mm×2.1 mm,1.7μm)进行液相色谱-串联质谱分析,采用多反应监测(MRM)、正离子模式和内标法定量,同时对线性范围、准确度、精密度和加标回收率等进行方法学验证。结果表明,在优化的条件下,赭曲霉毒素A、B和C在0.25~2.5 ng/mL线性范围内线性良好,决定系数均在0.999以上,本方法对赭曲霉毒素的检出限(LODs,S/N=3)和定量限(LOQs,S/N=10)分别为0.003~0.018、0.011~0.059μg/kg;在2.0~10.0μg/kg三个加标水平下,方法的平均回收率为80.50%~107.08%,相对偏差(RSDs)介于0.14%~4.94%(n=6)。利用此方法对10个批次的粮食及其制品进行检测,发现1个批次的样品检出赭曲霉毒素A,含量为(0.35±0.01)μg/kg。此方法操作简便、灵敏度高,适用于粮食及其制品中赭曲霉毒素A、B和C的检测。

A method for the simultaneous determination of the ochratoxins A,B and C in cereals and its products by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)with isotope internal standard was established. Samples were extracted by acetonitrile-water(84∶16,V/V),after shocked and centrifuged steps,the supernatant were enriched and purified through the immunoaffinity column of ochratoxin. Finally the supernatant was detected by HPLC-MS/MS method using Waters ACQUITY BEH C18(50 mm×2.1 mm,1.7 μm),and analyzed by multiple reaction monitoring(MRM)mode under positive electro-spry ionization(ESI+)with internal standard method. This method was quantified by OTA-13C20,which used as an internal standard. Results showed that,under the optimized conditions,ochratoxin A,B and C showed good linearity in the linear range of 0.25~2.5 ng/mL,and the determination coefficients were all above 0.999.The limits of detections(LODs,S/N=3)and the limits of quantification(LOQs,S/N=10)were 0.003~0.018 μg/kg and 0.011~0.059 μg/kg,respectively. The recovery rates of 3 kinds of cereals and its products with 3 spiked levels(2.0~10.0 μg/kg)were 80.50%~107.08%,and the relative standard deviations(RSDs)were 0.14%~4.94%(n=6). When ten samples were tested by this method,only one sample was detected of OTA with the content of(0.35±0.01) μg/kg. This paper proposed a method which is simple and easy,sensitive and suitable for determination of ochratoxins in cereals and its products.