Zhang Rong, Chen Yue, Zheng Pei, Dai Ying, Li Shasha, Jia Yingyi, Xie Ran, Wang Jinhua
1. Science and Technology Research Centre of China Customs，Beijing 100026，China.
2. Shandong Police College，Jinan 250200，China.
Se Pu. 2023 Feb;41(2):178-186. doi: 10.3724/SP.J.1123.2022.03042.
With the growing global popularity of traditional medicine and natural drugs， especially in Southeast Asia， the quality of traditional Chinese medicines （TCMs） has attracted the attention of regulators. China's major TCM export destinations， such as South Korea， Japan， and Europe， have formulated strict maximum residue limits （MRLs） of pesticides in TCMs. Therefore， a sensitive and high-throughput method for the simultaneous determination of 101 pesticide residues in and extracts of was established， involving gel permeation chromatography （GPC） coupled with gas chromatography-ion trap mass spectrometry （GC-ITMS）. In this method， the samples were first ground into fine powder and extracted twice with 20 mL acetonitrile in an ultrasonic cleaner for 30 min. After centrifugation for 10 min at 6000 r/min， the supernatants were combined and dried at 40 ℃ using a rotary vacuum evaporator. The residue was re-dissolved in 2 mL ethyl acetate-cyclohexane （1∶1， v/v） and purified by gel permeation chromatography using a 40 cm×20 mm column. The eluent collecting time was optimized as 17-30 min to ensure both the recovery of target compounds and the removal of interferences such as pigments and lipids from the target compounds. The eluent was then dried and re-dissolved with 1 mL toluene for analysis. The 101 pesticide residues were separated using the DB-5MS capillary column and analyzed by ion trap mass spectrometry. The pretreatment conditions and ion trap mass spectrometry parameters were optimized to effectively reduce the interference of complex TCM matrices and greatly improve the quantitative accuracy of the analysis and recovery of the target pesticides. Three spiked levels of 101 pesticides were tested. The average recovery range was 58.3%-108.9% and the relative standard deviations （RSDs） at the three spiked levels （=10） ranged from 0.4% to 16.5%. The limits of detection （LODs， =3） of the 101 pesticide compounds ranged from 0.2 to 40.0 μg/kg， while the limits of quantification （LOQs， =10） ranged from 0.6 to 120.0 μg/kg， which met the maximum residue limits of China's main TCM export countries and organizations. This rapid analysis method was easy to operate and high throughput， with strong sensitivity and good repeatability. The employment of gel permeation chromatography overcame the drawback of inadequate cleanup of the solid phase extraction column during TCM analysis. The application of ion trap technology further eliminated the interference of matrix impurities and increased the accuracy of the quantitative and qualitative analyses. This method fills the knowledge gap in multiple pesticide residue determination in TCMs using gas chromatography-ion trap mass spectrometry and is a useful and beneficial alternative to current analytical methods of TCMs.
随着传统医学和天然药物在全球范围内日益普及，尤其是在东南亚地区，中药的质量已引起监管机构的关注。中国主要的中药出口目的地，如韩国、日本和欧洲，已制定了严格的中药农药最大残留限量（MRLs）。因此，建立了一种同时测定中药材及其提取物中101种农药残留的灵敏且高通量的方法，该方法涉及凝胶渗透色谱（GPC）与气相色谱-离子阱质谱（GC-ITMS）联用。在此方法中，首先将样品研磨成细粉，在超声清洗器中用20 mL乙腈提取两次，每次30分钟。以6000 r/min离心10分钟后，合并上清液，并用旋转真空蒸发器在40℃下干燥。残留物重新溶解于2 mL乙酸乙酯-环己烷（1∶1，v/v）中，并使用40 cm×20 mm的柱通过凝胶渗透色谱进行纯化。优化洗脱液收集时间为17 - 30分钟，以确保目标化合物的回收率以及去除目标化合物中的色素和脂质等干扰物。然后将洗脱液干燥，并用1 mL甲苯重新溶解以进行分析。使用DB - 5MS毛细管柱分离101种农药残留，并通过离子阱质谱进行分析。对预处理条件和离子阱质谱参数进行了优化，以有效减少复杂中药基质的干扰，并大大提高目标农药分析和回收率的定量准确性。测试了101种农药的三个加标水平。平均回收率范围为58.3% - 108.9%，三个加标水平（n = 10）下的相对标准偏差（RSDs）范围为0.4%至16.5%。101种农药化合物的检测限（LODs，n = 3）范围为0.2至40.0 μg/kg，而定量限（LOQs，n = 10）范围为0.6至120.0 μg/kg，符合中国主要中药出口国家和组织的最大残留限量。这种快速分析方法操作简便、高通量，具有很强的灵敏度和良好的重复性。凝胶渗透色谱的应用克服了中药分析过程中固相萃取柱净化不充分的缺点。离子阱技术的应用进一步消除了基质杂质的干扰，提高了定量和定性分析的准确性。该方法填补了使用气相色谱-离子阱质谱测定中药中多种农药残留的知识空白，是目前中药分析方法的一种有用且有益的替代方法。
