Gas Chromatographic Analysis on Residual Difenoconazole in Apple and Soil

사과와 토양 중에서 Difenoconazole의 잔류성에 대한 기체 크로마토그래피 분석

The optimum conditions for the analysis of the difenoconazole fungicide on soil and crops were investigated and the residues of that in apple and soil were identified by using the gas chromatography. The extract with acetonitrile was separated with saturated NaCl and n-hexane solution after filtered, and concentrated. Obtained fungicide residues were transfered to the florisil column and eluted with acetone and n-hexane mixed solution for the analysis by GLC(ECD). From the standard addition experiments with 0.20 and 1.0ppm, the average recoveries were 86~92% and the detection limit was 0.01 ppm. It seems to be safely used when difenoconazole is treated three times until 15 days before harvest of apple. In this case residual amounts of difenoconazole in apple was from 0.037ppm to 0.044ppm. The soil samples extracted with methanol and ammonium hydroxide mixed solution were partitioned with dichloromethane and saturated sodium chloride solution. The organic phase was concentrated and redissolved with toluene and analyzed with GLC(FID) after cleaned with Sep-Pak column. From the standard addition experiments with 0.10, 0.50 and 1.0ppm, the average recoveries were 101.2~103.7% and the detection limit was 0.025ppm.

기체 크로마토그래피법을 이용하여 과수 재배용 살균제인 difenoconazole의 분석을 위한 최적 조건을 구하고, 사과와 토양 중에서의 잔류성을 조사하였다. 사과사료는 5% NaCl과 n-hexane액으로 분리, 농축하여 florisil column상에서 acetone과 n-hexane 혼합액으로 정제하여 GLC(ECD)로 분석하였다. 0.20과 1.0ppm의 표준물 첨가실험결과 평균회수율은 86.0~92.0% 였고, 검출한계는 0.01ppm 이었다. 사과에 대한 안정 사용기간은 수확 15일 전 3회 사용이 적당한 것으로 나타났으며, 이 경우 difenoconazole의 잔류량은 0.037ppm에서 0.044ppm 이었다. 토양시료를 methanol과 ammonium hydroxide 의 혼합액으로 추출하여 여과한 후 포화 NaCl 용액과 dichloromethane층으로 분배하였다. 유기층을 농축하여 toluene 용매로 재용해하였고, Sep-Pak column으로 정제한 후 GLC(FID)로 분석하였다. 0.10, 0.50과 1.0ppm 표준물 첨가실험 결과 평균 회수율은 101.2~103.7% 였고, 검출한계는 0.025ppm 이었다.