질량분석기를 이용한 농산물 중의 Glufosinate의 정량

임채욱 ( Chaiuk Lim ),박혜진 ( Hyejin Park ),백은주 ( Eunjoo Baek ),신병곤 ( Byeung Gon Shin ),조순길 ( Soon-kil Cho ) 한국환경농학회 2022 한국환경농학회 학술대회집 Vol.2022 No.-

Glufosinate is phosphorus-containing ammonium type that is widely used as crop protection for food crops and also in oil palm planations. Due to zwitterionic nature, previously reported methods for determination of glufosinate usually require derivatization. A fast and simple quantitative method for analysis of glufosinate in agricultural products has been developed. Glufosinate was determined by liquid chromatography tandem mass spectrometry and was extracted from matrices with methanol containing 1% formic acid on quick polar pesticides (QuPPe) method. Recovery experiments were conducted on pepper, brown rice and mandarin. Key performance parameters investigated were linearity, recovery, relative standard deviation (RSD), limit of detection, and limit of quantitation. The recoveries were within 76.9∼100.6% with relative standard deviation (RSD) of 2.5∼16.8% and the limit of quantification (LOQ) of methods were below 0.01 mg/kg, and the coefficient of determination (R²) of matrix-matched standards were > 0.995. The results obtained demonstrated that the method has achieved the requirements of the criteria for acceptance of single laboratory method validation.

퀘쳐스 전처리와 질량분석기를 이용한 논과 밭 토양 중 463종 다성분 분석법 정립 및 검증

백은주 ( Eunjoo Baek ),박혜진 ( Hyejin Park ),임채욱 ( Chaiuk Lim ),신병곤 ( Byeung Gon Shin ),조순길 ( Soon-kil Cho ),홍성희 ( Sung-hee Hong ) 한국환경농학회 2022 한국환경농학회 학술대회집 Vol.2022 No.-

Residual pesticides remaining in the soil may be absorbed and transferred to crops, causing unintentional contamination of agricultural products. So, proper management of the cultivation environment such as soils must be preceded. It is necessary to establish an analytical method to accurately and reliably analyze residual pesticides in paddy and unpland soils. In this study, a QuEChERS method for simultaneous determination of 463 pesticide residues in paddy and upland soils was developed and validated. Soil samples were extracted using a modified QuEChERS.. And then targeted pesticides were purified following the dispersive solid phase extraction(d-SPE, PSA) cleanup method and detected by liquid and gas chromatography-tandem mass spectrometry(LC-MS/MS and GC-MS/MS). To evaluate performance of the method, validation experiments were carried out on paddy and unpland soils at three spiking levels (0.01, 0.05, 0.1 mg kg^-1). The recoveries of the paddy soil ranged between 70.15 and 120.0% with associated relative standard deviations(RSD) less than 22% for the 445 pesticides. The recoveries of the unpland soil ranged between 70.62 and 115.5% with associated relative standard deviations(RSD) less than 22% for the 449 pesticides. The limit of quantification (LOQ) of methods were below 0.01 mg/kg^-1, and the coefficient of determination (R²) of matrix-matched standards were > 0.997. In order for the developed method to be certified as an analytical method determined by the head of NAQs, cross-validation of the three labs is in progress.

퀘쳐스 전처리와 질량분석기를 이용한 과일봉지와 버섯배지 중 463종 다성분 분석법 정립 및 검증

박혜진 ( Hyejin Park ),임채욱 ( Chaiuk Lim ),백은주 ( Eunjoo Baek ),신병곤 ( Byeung Gon Shin ),조순길 ( Soon-kil Cho ),홍성희 ( Sung-hee Hong ) 한국환경농학회 2022 한국환경농학회 학술대회집 Vol.2022 No.-

For the safety management of agricultural products, proper management of the cultivation environment such as agricultural materials(e.g. fruit bags, mushroom culture media, and so on), soils, and agricultural water must be preceded. It is necessary to establish analytical method to accurately and reliably analyze residual pesticides in the cultivation environment. In this study, a QuEChERS method for simultaneous determination of 463 pesticide residues in fruit bags and mushroom culture media was developed and validated. The samples were initially extracted with acetonitrile using of partitioning salts composed trisodiumcitrate dihydrate, disodium hydrogencitrate sesquinhydrate, NaCl, and MgSO₄. And then targeted pesticides were purified following the dispersive solid phase extraction(d-SPE, PSA) cleanup method and detected by liquid and gas chromatography-tandem mass spectrometry(LC-MS/MS and GC-MS/MS). To evaluate performance of the method, validation experiments were carried out on fruit bags and mushroom culture media at three spiking levels (0.01, 0.05, 0.1 mg kg^-1). The recoveries of the fruit bags ranged between 70.3 and 120.0% with associated relative standard deviations(RSD) less than 22% for the 458 pesticides. The recoveries of the mushroom culture media ranged between 70.5 and 120.0% with associated relative standard deviations(RSD) less than 22% for the 453 pesticides. The limit of quantification (LOQ) of methods were below 0.01 mg/kg^-1, and the coefficient of determination (R²) of matrix-matched standards were > 0.997. In order for the developed method to be certified as an analytical method determined by the head of NAQs, cross-validation of the three labs is in progress.

질량분석기를 이용한 농산물 중의 Acetochlor 대사산물, EMA와 HEMA의 정량

임채욱 ( Chaiuk Lim ),박혜진 ( Hyejin Park ),백은주 ( Eunjoo Baek ),윤지민 ( Jimin Yoon ),이주령 ( Juryeong Lee ),신병곤 ( Byeung Gon Shin ),조순길 ( Soon-kil Cho ) 한국환경농학회 2021 한국환경농학회 학술대회집 Vol.2021 No.-

Acetochlor is a selective herbicide that controls a broad spectrum of annual grasses, sedge, and broadleaf weeds primarily in corn. MRLs are established for the combined residues of acetochlor and its ethyl methyl aniline-(EMA) and hydroxyethyl methyl aniline-(HEMA) producing metabolites, expressed as acetochlor equivalents. A fast and simple quantitative method for analysis of metabolites of acetochlor, EMA and HEMA in agricultural products has been developed. EMA was determined by gas chromatography tandem mass spectrometry and HEMA by liquid chromatography tandem mass spectrometry. Two compounds were extracted from matrices with acetonitrile containing 1% formic acid and the use of partitioning salts composed of NaCl and MgSO₄ based on QuEChERS method. Recovery experiments were conducted on pepper, brown rice and mandarin. Key performance parameters investigated were linearity, recovery, relative standard deviation(RSD), limit of detection, and limit of quantitation. The recoveries were within 70.6∼106.8% with relative standard deviation (RSD) of 0.7∼7.3% and the limit of quantification (LOQ) of methods were below 0.01 mg/kg, and the correlation coefficient (r²) of matrix-matched standards were > 0.995.

Fluopyram의 전작물 유래 및 나지조건 토양잔류성에 기초한 알타리무의 식물식재후방기간

김영은 ( Young Eun Kim ),윤지현 ( Ji Hyun Yoon ),임다정 ( Da Jung Lim ),김선욱 ( Seon Wook Kim ),조현정 ( Hyunjeong Cho ),신병곤 ( Byeung Gon Shin ),김효영 ( Hyo Young Kim ),김인선 ( In Seon Kim ) 한국환경농학회 2021 한국환경농학회지 Vol.40 No.2

BACKGROUND: Pesticide uptake by a rotational crop after being used for the primary crop is a potential cause of violation against the pesticide law if the pesticide is not registered in the secondary crop. This study was conducted to investigate the plant back interval (PBI) of fluopyram for the rotational cultivation of radish. METHODS AND RESULTS: Two experimental approaches were performed the evaluation of residues in radish cultivated successively in soil 16 days after treated with fluopyram onto pepper plant (T1) and in radish cultivated in bare soil treated with fluopyram at PBI 30 and PBI 60 days (T2). A modified QuEChERS method coupled with LC/MS/MS analysis showed good linearity of matrixmatched standard calibration of fluopyram with the coefficient values of determination greater than 0.995. Recovery values at levels of 0.01, 0.05, 0.1 and 0.25 mg/kg ranged from average 84.9 to 117.6% with RSD less than 10%. Fluopyram residues in radish harvested from T1 and T2 were found as levels less than maximum residue limit. CONCLUSION: This study suggests 20~30 days as the PBI of fluopyram for the rotational cultivation of radish in the greenhouse soil treated with fluopyram used for pepper as the primary crop.

퀘쳐스 전처리와 LC-MS/MS를 이용한 Thiodicarb와 Methomyl의 정량

박혜진 ( Hyejin Park ),임채욱 ( Chaiuk Lim ),백은주 ( Eunjoo Baek ),윤지민 ( Jimin Yoon ),이주령 ( Juryeong Lee ),신병곤 ( Byeung Gon Shin ),조순길 ( Soon-kil Cho ) 한국환경농학회 2021 한국환경농학회 학술대회집 Vol.2021 No.-

Both methomyl and thiodicarb belong to the group of oxime carbamate insecticides that acts by inhibiting acetylcholinesterase activity. The residue definition set in MRL regulation for all agricultural commodities is the sum of methomyl and thiodicarb, expressed as methomyl. Thiodicarb consists essentially of two methomyl moieties joined through their amino nitrogen by sulfur. Stoichiometry has to be applied to the calculus of the concentration, and the conversion factor of thiodicarb has to be multiplied by two. A Liquid chromatography tandem mass spectrometry was used for the simultaneous determination of thiodicarb and its degradation product methomyl as a total residue of thiodicarb in brown rice. Thiodicarb is known to degraded during analysis; therefore, a through investigation was carried out, revealing that thiodicarb degrades to methomyl immediately after spiking into a matrix of grain product. Two compounds were extracted from brown rice with acetonitrile containing 1% formic acid and the use of partitioning salts composed of NaCl and MgSO₄ based on QuEChERS method. Recovery experiments were conducted on brown rice. Main performance parameters investigated were linearity, recovery, relative standard deviation(RSD), limit of detection, and limit of quantitation. The recoveries were within 72.2∼96.0% with relative standard deviation (RSD) of 0.5∼2.3% and the limit of quantification (LOQ) of methods were below 0.01 mg/kg, and the coefficient of determination (R²) of matrix-matched standards were > 0.997.