摘要
建立了茶叶中18种有机氯和9种拟除虫菊酯农药残留微波辅助萃取-气相色谱分析方法。运用正交设计法对微波萃取条件进行了优化,茶叶样品用正己烷-二氯甲烷混合溶剂(1:2,V/V)进行萃取,萃取液用弗罗里硅土和中性氧化铝混合层析柱净化,采用J&WDB-1701毛细管柱分离,GC-ECD法同时测定。在0.4、0.2、0.1ml(0.5μg/ml有机氯农药+1.0μg/ml拟除虫菊酯农药)三个水平添加时的平均回收率(n=5)分别为80.9%～118.5%、88.4%～120.7%、80.9%～116.3%;相对标准偏差分别为2.09%～6.70%、1.89%～6.49%、1.98%～11.87%。该方法的检出限为:有机氯农药0.0004～0.0048mg/kg,拟除虫菊酯农药0.0033～0.0400mg/kg。
A new method for multiresidue analysis of 18 organochlorines and 9 pyrethroids in tea from Jiangxi province was established. The pesticide residues were extracted from tea samples with hexane-dichloromethane （1：2, V/V） by using microwaveassisted methed, and the microwave-assisted extraction conditions, such as the extraction solvent type, volume, microwave heating time and microwave temperature were optimized with orthogonal test design. The extracts were purified with alumina neutral-florisil column, and then determined with gas chromatography equipped with electron-capture detector （GC-ECD）, using DB-1701 capillary column. The recoveries obtained from Chinese tea samples （n=5） added with pesticide standards at the three levels of 0.4, 0.2 and 0.1 ml （0.5 μg/ml organochlorines plus 1.0 μg/ml pyrethroids） are in the ranges of 80.9% to 118.5%, 88.4% to 120.7% and 80.9% to 116.3% with the RSDs in the ranges of 2.09% to 6.70%, 1.89% to 6.49% and 1.98% to 11.87%, respectively. The detection limits of the organochlorine pesticides are in the range of 0.0004 to 0.0015 mg/kg, and those of the pyrethroids are in the range of 0.0067 to 0.0365 mg/kg.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2008年第11期562-566,共5页
Food Science
基金
教育部"长江学者和创新团队发展计划"项目(IRT0540)
南昌大学食品科学教育部重点实验室开放基金项目(NCU200408)
