Determination of pyrethroid pesticides in tea by accelerated solvent extraction and ultra-performance liquid chromatography-tandem mass spectrometry
JIAO Huize1, LU Shiqing1, HOU Di2, ZHANG Qianqian2
1. State Key Testing Laboratory of Edible Bird's Nest and Nutritional Health Food(Qinzhou), Qinzhou Customs, Qinzhou 535000, China;
2. College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
A method was developed for the determination of pyrethroid pesticides in tea by accelerated solvent extraction (ASE) combined with ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The target compounds were extracted from tea using n-hexane and acetone (2:1, v/v) for 5 min at 10.34 MPa and 80℃ via a single cycle of accelerated solvent extraction. The extract was purified by GCB/NH2 and Florisil columns, analyzed by UPLC-MS/MS in positive electrospray ionization (ESI+) and multiple reaction monitoring (MRM) modes, and quantified by the external standard method. Regression analysis revealed that the linear relationships between mass concentration and peak area are significant for the 10 pyrethroid pesticides, and the correlation coefficients (r) are all not less than 0.9995. The limits of detection (LOD) of the 10 pyrethroid pesticides ranged from 0.5 μg/kg to 5.0 μg/kg and the limits of quantification (LOQ) ranged from 1.6 μg/kg to 16.6 μg/kg. The recoveries of all the pesticides ranged from 68.7% to 103.8% at the spiked levels of LOQ, 0.4 mg/kg and maximum residue limit (MRL) (added 1 mg/kg without MRL) with RSDs ranging from 0.8% to 13.2% (n=7). The proposed method is simple, rapid, sensitive, and accurate, and could be effective for trace analysis of pyrethroid pesticides in tea.
JIAO Huize,LU Shiqing,HOU Di et al. Determination of pyrethroid pesticides in tea by accelerated solvent extraction and ultra-performance liquid chromatography-tandem mass spectrometry[J]. Chinese Journal of Chromatography, 2019, 37(6): 605-611.