高效液相色谱-串联质谱法检测蜂花粉中赭曲霉毒素A残留量

Determination of ochratoxin A residue in bee pollen by high performance liquid chromatography-tandem mass spectrometry

目的建立蜂花粉中赭曲霉毒素A(ochratoxin A,OTA)的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。方法样品经乙腈提取,固相萃取柱富集净化后,采用HPLC-MS/MS对目标物进行定性确证和定量分析。在Leapsil C18(100 mm×3.0 mm,2.7μm)上以0.005 mol/L乙酸铵甲酸水溶液和乙腈为流动相进行梯度洗脱分离;质谱采集模式为电喷雾负离子监测模式。结果本方法的赭曲霉毒素A的定量限(以S/N=10计)为5μg/kg;在5~100μg/L的质量浓度范围内呈现良好的线性关系,相关系数(r)大于0.99。本底空白的玉米花粉、茶花粉、荷花粉、油菜花粉4种基质中5、10、20μg/kg添加水平下的加标回收率范围为84.6%~103.6%,精密度范围为5.1%~12.2%。结论本方法准确可靠、灵敏度高、经济实用,可替代较为昂贵的免疫亲和柱,较大降低检测成本,且适用于大部分蜂花粉基质的测定。

Objective To establish a method for the determination of ochratoxin A in pollen based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).Methods The sample was extracted by acetonitrileand cleaned up by solid phase extraction cartridge. The separation was carried out on a Leapsil C18(100 mm×3.0 mm, 2.7 μm) with a gradient elution using 0.005 mol/L ammonium acetate formic acid solution and acetonitrile as mobile phases. The analysis of ochratoxin A was performed under electrospray negative ionization mode.Results The limits of quantification (LOQ, S/N=10) was 5μg/kg. A good linearity (r >0.99) was achieved for the target compounds over the range of 5~100μg/L. The recoveries at the three spiked levels (5, 10, 20μg/kg) in the blank matrices such as corn pollen, camellia pollen, lotus pollen, and rape pollen, were varied from 84.6% to103.6% with the relative standard deviations varied from 5.1% to 12.2%. Conclusion The method is accurate, efficient, sensitive and practical. The cost of detection is obviously re-duced by replacing immunoaffinity column with HLB column which has the same purification effect. It can be applied to most of pollen which may be contaminated by Ochratoxin A.