본 연구에서는 GC-NPD/MS를 이용하여 농산물 중 국내 사용금지 고독성 유기인계 살충제 phosphamidon의 잔류 분석법을 확립하였다. 대표 농산물은 배추, 고추, 감귤, 현미 및 콩을 사용하였고, acetone으로 추출된 phosphamidon은 n-hexane 및 dichloromethane 액-액 분배법을 순차적으로 이용하고 silica gel 흡착크로마토그래피법으로 정제하여 GC-NPD/MS 의 분석시료로 사용하였다. Phosphamidon의 정량분석을 위한 최적 GC-NPD 분석조건을 확립하였으며, 정량한계(LOQ)는 0.02 mg/kg 이었다. 각 대표 농산물에 대해 정량한계, 정량한계의 10배, 50배 및 100배 수준에서 회수율을 검토한 결과, 모든 처리농도에서 84.9~100.7% 수준의 회수율을 나타내었으며, 반복 간 변이계수(CV)는 최대 4.9%를 나타내어 잔류분석 기준인 회수율 70~120% 및 분석오차 10% 이내를 충족시키는 만족한 결과를 도출하였으며, GC/MS SIM을 이용하여 실제 농산물 시료에 적용하여 재확인 하였다. 이상의 결과로 신규 phosphamidon의 GC-NPD/MS 분석법은 검출한계, 회수율 및 분석오차 면에서 국제적 분석기준을 만족하는 신뢰성이 확보된 정량분석법으로 사용 가능할 것이다.

Phosphamidon is a typical organophosphorus insecticide which has been used on various crops. The commercial compound of phosphamidon usually contains E- and Z-isomers on vinyl moiety of the molecule. Due to its highly polar nature comparing with most organophosphorus insecticides of mid- to non-polarity, it is desirable to apply separate method for the analysis of phosphamidon residues. This study was therefore conducted to establish an individual method for the phosphamidon residue in crops using GC-NPD/MS. The phosphamidon residue was extracted with acetone from representative samples of five raw products which comprised hulled rice, soybean, Kimchi cabbage, green pepper, and mandarin. The extract was diluted with saline water, and washed by n-hexane partition. Most of nonpolar co-extractives were removed, while phosphamidon still resided in the aqueous phase. Phosphamidon was then recovered from the aqueous phase by dichloromethane partition. Silica gel column chromatography was additionally employed for final clean up of the extract. Phosphamidon isomers were separated and quantitated by GLC with NPD, using DB-17 capillary column. Method validation was performed by recovery experiment on each crop fortified with phosphamidon at 4 levels in triplication. Approximately, the phosphamidon residues existed as a mixture of 90% Z- and 10% E-isomer type. Mean recoveries of total phosphamidon residues, containing approximately 90% Z- and 10% E-isomer, ranged from 84.9% to 100.7% in five agricultural commodities showing that the coefficients of variation were all less than 10%. Limit of quantitation of the method was 0.02 mg/kg, irrespective of crop types. A confirmatory technique using GC/MS with selected-ion monitoring was also provided to clearly identify the suspected residue. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of phosphamidon in import-export agricultural products.

ABSTRACT
서 언
재료 및 방법
    1. 시약 및 기구
    2. 농산물 시료
    3. GC-NPD/MS 분석 조건 확립
    4. 표준검량선 및 분석정량한계(Limit of quantitation,LOQ)
    5. 농산물 시료로 부터 phosphamidon의 추출 및 분배
    6. Silica gel 흡착 크로마토그래피
    7. 농산물 대표시료에 대한 phosphamidon의 회수율 검정
결과 및 고찰
    1. GC-NPD 분석조건의 확립
    2. 시료 중 phosphamidon의 추출 및 분배
    3. Silica gel 흡착 크로마토그래피 조건의 최적화
    4. 농산물 시료 중 phosphamidon의 분석 정량한계 및회수율
    5. GC/MS를 이용한 잔류분의 재확인
적 요
REFERENCES

• 정명근(강원대학교 생약자원개발학과) | Myoung-Gun Choung (Dept. of Herbal Medicine Resource, Kangwon National University) Corresponding author