No abstract

No abstract

A rapid, sensitive, and reliable method is presented for the determination of trace amounts of abamectin in lettuce and cucumber. Abamectin consists of >80% avermectin Bia and <20% avermectin Bib. Vegetables were extracted with ethyl acetate, and the extract was purified by solid-phase extraction using Sep-Pak silica cartridges. The purified extracts were analyzed by HPLC with a 5-µ Zorbax ODS column and UV detection under isocratic conditions. The method yields recoveries for avermectins Bia and Bib of 76-109% in the 0.054-0.54 mg/kg range. The limit of detection of the method is 40 µg of avermectins Bia and Bib/kg of vegetable.The avermectins, a newly discovered family of pesticidal agents, are macrocyclic lactones produced by the actinomycete Streptomyces avermitilis (Burg et al., 1979). The avermectin structures have been elucidated by Albers-Schónberget al. (1981), and some of the biological activities have been reviewed (Campbell et al., (1983). Abamectin is the commercial product that is being developed as an insecticide and acaricide with contact and stomach action. Abamectin consists of >80% avermectin Bi" and <20%

No abstract

No abstract