超高效液相色谱-串联质谱法检测螺旋藻保健品中7种微囊藻毒素

采用固相萃取净化结合超高效液相色谱-串联质谱法(UPLC-MS/MS)测定了螺旋藻保健品中7种微囊藻毒素(MCs)。螺旋藻保健品经70%(体积分数)的甲醇超声提取,冷冻离心沉淀杂质后,经HLB柱净化。在Waters ACQUITY UPLCBEH C18色谱柱上以乙腈和0.2 mmol/L乙酸铵水溶液为流动相进行梯度洗脱分离,采用电喷雾离子源正离子模式进行多反应离子监测,外标法定量。7种MC在线性范围内线性关系良好(相关系数(r)不小于0.995);检出限为6.7～33.3 μg/kg,定量限为20.0～100.0 μg/kg。各分析物在阴性螺旋藻保健品中的加标回收率在87.5%～97.9%之间,相对标准偏差(RSD)在1.6%～6.9%之间。该方法准确可靠,灵敏度高,可用于螺旋藻保健品中MC污染的确证定性、定量检测。

Determination of 7 microcystins in Spirulina health food products by ultra performance liquid chromatography-tandem mass spectrometry

Ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with solid phase extraction (SPE) has been developed for the determination of 7 microcystins (MCs) in Spirulina health food products. The sample was extracted by 70% (v/v) methanol. The lipid substances were isolated by centrifugation under freezing condition, and then followed by clean-up with a Waters Oasis HLB solid phase extraction cartridge. The separation was performed on a Waters ACQUITY UPLCBEH C18 column with gradient elution using acetonitrile and 0.2 mmol/L ammonium acetate. The electrospray ionization (ESI) source in positive ion mode was used for multiple reaction monitoring (MRM). The external standard method was used for the quantification. The linear ranges for 7 MCs were 20-400 μg/kg, and the correlation coefficients were not less than 0.995. The limits of detection were 6.7-33.3 μg/kg. The limits of quantification were 20.0-100.0 μg/kg. The recoveries of the 7 MCs spiked in blank Spirulina samples ranged from 87.5% to 97.9% with the relative standard deviations of 1.6%-6.9%. The results demonstrated that the method is easy, fast, sensitive, and suitable for the confirmation and quantification of the 7 MCs in Spirulina samples.