Abstract
A method for the multiresidual simultaneous analysis of 11 thiocarbamates was studied using HPLC. Thiocarbamate in Chinese cabbage was analyzed in the order of extraction, partition, and cleanup in their optimum condition. Acetone was chosen as an extracting solvent. As a partitioning solvent, the mixture of 50% methylene chloride and petroleum ether containing extremely small water content showed good recoveries of thiocarbamate from the water layer. Partition efficiency was affected by pH of the water layer; it remained almost constant under the acidic and neutral condition while decreasing under the basic condition. The comparison done in cleanup step showed that the column chromatographic method is superior to the treatment of coagulating reagent. As an absorbent, the mixture of charcoal, magnesia, and celite with the ratio of 1 : 2 : 4 gave better recoveries and also effectively removed chlorophyll. Over the total procedure, the average recoveries for thiocarbamates in Chinese cabbage were 91% at about 2 ppm fortification level within the relative standard deviation of 8%, and the minimum detection limit (MDL) was 2.2${\sim}$9.3 ng.
HPLC로 11종의 티오카바메이트들의 다성분 동시분석법을 연구하였다. 배추시료에 넣은 티오카바메이트는 추출, 분배, 세척, 및 분리-검출이 단계로 분석되는데, 추출용매로서는 아세톤을 선택하였고, 분배용매로서는 50% 염화메틸렌/석유에테르 혼합용매가 좋은 회수율을 보였다. 분배효율은 물층의 pH 영향을 받는데 산성 혹은 중성에서는 영향이 없으나 염기성에서는 감소하였다. 세척단계에서 공추출물의 제거효율은 응고액 처리법 보다는 컬럼 크로마토그래피법이 우수하였다. 흡착제로는 활성탄/마그네시마/셀라이트 1/2/4)의 흡착제가 좋은 효율을 보였으며, 클로로필드 효과적으로 제거되었다. 이 방법으로 배추에 있는 2ppm정도의 티오카바메이트의 동시 분석의 결과는 평균회수율이 91%, 상대표준편차가 약 8%, 검출한계가 2.2${\sim}$9.3ng이었다.
