Abstract
Isotianil is a novel fungicide which induces systemic acquired resistance in plants. It has excellent preventive effects as low dosages against rice blast which is one of the most serious diseases in rice. The Maximum Residue Limit (MRL) of Isotianil in republic of korea was set to 0.1 mg/kg in rice, so it is necessary to determine levels of Isotianil residues in agricultural commodities for controlling food safety. Therefore, The purpose of this study was to develop analytical method for the determination of isotiical residues in agricultural commodities using GC-NPD/MSD. Isotianil was extracted with acetonitrile from apple, chinese cabbage, hulled rice, mandarin, pepper, and soybean. The extract was diluted with saline water, and then dichloromethane partition was followed to recover this fungcide from the aqueous phase. A solid phase extraction with Florisil cartridge was additionally employed for final clean up. Isotianil was analyzed and quantitated by GC-NPD and confirmed by GC-MSD. Average recovery of Isotianil ranged from 70.0 to 103.9% in six representative agricultural commodities with relative standard deviations less than 10%, and limit of quantification (LOQ) was 0.05 mg/kg.
Isotianil은 쌀 도열병을 방제하기 위한 새로이 개발된 식물활성 살균제로 다른 식물활성제에 비해 소량으로도 장시간의 효과를 나타내는 특징을 가지고 있다. 신규 농약 Isotianil에 대한 기준은 국내의 경우 2010년 쌀에 대하여 0.1 mg/kg으로 최초 설정되었으며, 이에 따른 식품 중 안전관리를 위해 Isotianil을 분석하기위한 검사법을 개발하였다. 검체 일정량에 acetonitrile을 가하고 균질화하여 대상농약을 추출하였으며, 액-액분배하고 florisil 카트리지를 이용한 고체상 추출 후 GC-NPD 및 GC-MSD로 분석하였다. 분석결과 농산물에 의한 간섭물질은 없었으며, 대표 농산물 현미 등 6 종에 대한 Isotianil의 분석 시험법의 정량한계와 직선성은 각각 0.05 mg/kg과 0.999($r^2$)이었다. 회수율은 대표 농산물에서 70.0~103.9%이었으며, 분석오차는 10% 미만으로 CODEX 잔류분석 기준에 적합하였다.