액-액 분배법을 활용한 작물 중 pymetrozine의 잔류분석법 확립

Abstract

Abstract Polar pesticides like pymetrozine (log P ow : -0.18) are known to be difficult to analyze. Theanalytical method of pymetrozine using hydromatrix included in the official method of KFDA wasuncommon and provided ambiguous evidence to confirm both the identity and the quantity. Therefore, precisesingle residue analytical method was developed in representative crops for using liquid-liquid extraction(LLE). The pymetrozine residue was extracted with methanol from 11 representative crops which comprisedapple, blueberry, broccoli, cabbage, cherry, crown daisy, hulled rice, Korean cabbage, potato, rice andwatermelon. The extract was purified serially by liquid-liquid extraction (LLE) and silica solid phaseextraction (SPE). For rice and hulled rice samples, n-hexane partition was additionally adopted to removenonpolar interferences, mainly lipids. The residue levels were analyzed by HPLC with DAD, using C 8 column. LOQ (limit of quantitation) of pymetroizinie was 1 ng (S/N > 10) and MQL (method quantitationlimit) was 0.01 mg/kg. Mean recoveries from 11 crop samples fortified at three levels (MQL, 10× MQL and50 × MQL) in triplicate were in the range of 83.1~98.5% with coefficients of variation (CV) of less than10%, regardless of sample type, which satisfies the criteria of KFDA. The method established in this studycould be applied to most of crops as an official and general method for analysis of pymetrozine residue.Key words Analysis, LLE (liquid-liquid extraction), Pymetrozine, Residue