QuEChERS-超高效液相色谱-三重四极杆质谱测定野生食用菌中尼古丁

云南省拥有大量的野生食用菌资源,其中内源性的尼古丁近年来受到了广泛的关注。该研究以野生食用菌为研究对象,将QuEChERS方法进行改进,优化了提取溶剂、净化条件等,并针对尼古丁在超高效液相色谱不同流动相条件下的色谱行为进行优化,结合三重四极杆质谱仪,建立了测定野生食用菌中尼古丁的高效、快速、高灵敏的方法。结果表明,氨水-乙腈(6∶94, v/v)混合溶液能够较好地提取野生食用菌中的尼古丁,提取溶液经石墨化碳黑(GCB)和N-丙基乙二胺(PSA)混合填料净化后,利用0.1%(体积分数)氨水溶液和乙腈作为流动相,正离子多反应监测(MRM)模式下,得到的尼古丁色谱峰形较好,响应较高。尼古丁在0.05～50.0μg/L范围内线性关系良好,相关系数(r^2)为0.999 9,定量限为0.2μg/kg,检出限为0.05μg/kg。3个加标浓度下的平均回收率为86.3%～96.4%,相对标准偏差为4.4%～6.3%。该方法的灵敏度和回收率均符合食用菌产业中尼古丁的快速测定要求。

Determination of nicotine in wild edible fungi by QuEChERS-ultra performance liquid chromatography-triple quadrupole mass spectrometry

Yunnan Province has many wild edible fungi resources, and of these, endogenous nicotine has received extensive attention in recent years. In this study, wild edible fungus was used as the research object, and the QuEChERS method was improved, including optimization of solvent extraction and purification conditions and optimization of the chromatographic behavior of nicotine under different mobile phase conditions for ultra performance liquid chromatography (UPLC). Combined with triple quadrupole mass spectrometry, a high-efficiency, rapid, and sensitive method for the determination of nicotine in wild edible fungi was established. The results showed that an ammonia:acetonitrile (6:94, v/v) mixed solution can completely extract nicotine from wild edible fungi, and the extraction solution was purified by graphitized carbon black (GCB) and N-propylethylenediamine (PSA) mixed filler. Then, a 0.1% (volume percentage) ammonia solution and acetonitrile were used as the mobile phases. The nicotine peak obtained in the positive ion multiple reaction monitoring (MRM) mode had a better peak shape and better response. The linear relationship of nicotine mass concentration with peak area in the range of 0.05-50.0 μg/L was good. The correlation coefficient (r²) was 0.9999. The limit of quantification was 0.2 μg/kg, and the limit of detection was 0.05 μg/kg. The average recovery rates at three spiked concentrations were in the range of 86.34%-96.4%, and the relative standard deviations varied from 4.44% to 6.3%. The sensitivity and recovery of this method are consistent with the rapid determination of nicotine in the edible fungus industry.