摘要
研究了金属Al3+沉淀茶多酚净化茶叶基质的条件,探索茶叶中呋虫胺、烯啶虫胺、噻虫嗪、吡虫啉、噻虫胺、氯噻啉、啶虫脒和噻虫啉烟碱类农药多残留的液相色谱测定方法。茶叶经乙腈提取,以200 g·L-1AlCl3为沉淀剂,并用1 mol·L-1NaOH调节pH值,再经Carb-PSA柱净化,乙腈洗脱,最后用甲醇-水(体积比为1∶9)溶解,高效液相色谱紫外检测器检测,验证该方法的可行性。结果表明:在添加0.1~1.0 mg·kg-1的水平下,除烯啶虫胺外,7种烟碱类农药的平均回收率为75%~110%,相对标准偏差(RSD)≤12.3%。本方法操作简单,可满足茶叶中烟碱类农药多残留分析的要求。
By optimizing the conditions of using AlCl3 precipitation method optimized for cleaning up the tea extract, a new sensitive high performance liquid chromatography （ HPLC ） method was developed for the simuhaneous determination of neonicotinoid insecticides in tea, including dinotefuran, nitenpyram, thiamethoxam, imidacloprid, clothianidin, imidaclothiz, acetamiprid and thiaeloprid. Tea samples were extracted with aeetonitrile and the extract was cbtained by filtration then the right amount of 200 g. L-1 AlCl3 was added to it as precipitating agent, followed by 1 mol-L-1 NaOH used to adjust pH. Then it was cleaned up with Carb-PSA cartridge. Neonicotinoid insecticides were eluted with acetonitrile and dried extract was dissolved with methanol-water（ 1：9, V/V） , and finally analyzed with HPLC coupled with ultraviolet detector. The results show that the recoveries of 7 neonicotinoid insecticides except nitenpyram in tea sample ranged from 75% to 110% at the spiked level of 0. 1 - 1.0 mg kg-1 , with relative standard deviations （ RSD ）less than 12.3 %. The established method was simple, sensitive and accurate, and could be used for monitoring neo- nicotinoid insecticides in tea.
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2013年第6期123-127,共5页
Journal of Nanjing Agricultural University
基金
国家自然科学基金项目(31270728)
国家科技部星火计划项目(2012GA710001)
