Agricultural Product Samples Research Articles

LC-MS/MS를 이용한 농산물 중 pyrimisulfan 잔류량 분석법 개발 및 확인

국내 신규 제초제로 등록된 pyrimisulfan에 대해 농산물 중 잔류실태를 조사하기 위하여 LC-MS/MS를 이용한 시험법을 개발하였다. Pyrimisulfan 시험법의 회수율은 현미, 감자, 감귤, 고추에서 0.005 mg/kg 수준에서 88.7~99.3%이고 0.05 mg/kg수준에서 각각 90.1~94.2%였다. 회수율에 대한 모든 분석오차는 10% 미만으로 Codex 잔류물질 분석 가이드라인에 만족하였다.16 분석을 위한 기기 조건에서 pyrimisulfan의 정량한계는 0.005 mg/kg이었으며 0.01~1.0 mg/kg 범위에서 상관계수(R) 0.999 이상의 높은 직선성을 보여주었다. 따라서 본 연구에서 개발된 잔류농약 시험법은 농산물을 대상으로 효과적인 시료 전처리 방법과 최적의 정제 과정을 확립하여 다양한 농산물에 대한 잔류량 검출이 적당함을 확인할 수 있었다. 이와 같이 확립한 pyrimisulfan의 잔류시험법은 국제적 분석 기준을 만족할 뿐만 아니라 분석과정의 신뢰성 또한 확보할 수 있어서 본 잔류농약 시험법은 공정시험법으로 사용 될 것이다. The maximum residue limits of pyrimisulfan is set as 0.05 mg/kg in rice in 2011, so very reliable and sensitive analytical method for pyrimisulfan residues is required for ensuring the food safety of pyrimisulfan residues in agricultural products. In this study, a rapid and sensitive analytical method was developed and validated using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS) for the determination of herbicide pyrimisulfan residues in agricultural products. Average recoveries of pyrimisulfan ranged from 88.7 to 99.3% at the spiked level of 0.005 mg/kg and from 90.1 to 94.2% at the spiked level of 0.05 mg/kg, while the relative standard deviation was less than 10%. Linear range of pyrimisulfan was between 0.01~1.0 <TEX>${\mu}g/mL$</TEX> with the correlation coefficient (<TEX>$r^2$</TEX>) 0.999 and limit of quantification was 0.005 mg/kg. The results of method validation were satisfied Codex guideline. The results revealed that the developed and validated analytical method is possible for pyrimisulfan determination in agricultural product samples and will be used as an official analytical method.

Development and Validation of Analytical Methods for Picoxystrobin Determination in Agricultural Products by GC-ECD and GC-MS

농산물 중에 있는 Picoxystrobin 잔류량을 검사하기 위해 가스크로마토그래프-전자포획검출기와 가스크로마토그래프-질량분석기를 이용한 간단하고 감도가 좋은 분석방법을 개발하였다. Picoxystrobin 잔류물은 acetonitrile 추출, 포화식염수를 이용한 액-액 분배, florisil 카트리지 정제 과정을 거쳐 기기분석을 수행하였다. 개발된 방법으로 Picoxystrobin 잔류허용기준이 설정된 식품인 고추와 사과 외 대표 농산물 시료 현미, 대두, 버섯, 감귤을 대상으로 농약을 0.02, 0.05, 0.5 mg/kg 농도로 처리하여 회수율을 시험한 결과는 64.0~98.3%이었으며, 상대표준편차는 10% 미만이었다. 검량선 작성을 위해 0.1~5 mg/L 범위로 표준품을 만들어 실험한 결과 상관계수(<TEX>$r^2$</TEX>)는 0.999로 높은 직선성을 보였으며, 분석방법의 검출한계와 정량한계는 각각 0.005와 0.02 mg/kg이었다. 또한 확인시험을 위하여 질량분석기를 사용하였으며, 145와 335를 특성이온으로 선정하였다. A simple and sensitive analytical method was developed using gas chromatography with electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS) for determination of Picoxystrobin in agricultural products (apple, hulled rice, mushroom, pepper, soybean, and mandarin). Picoxystrobin residues were extracted with acetonitrile, partitioned with saline water, and then they were cleaned up on a florisil solid-phase extraction (SPE) cartridge to obtain an extract suitable for analysis by GC-ECD and GC-MS. The method was validated using 6 agricultural product samples spiked with Picoxystrobin at different concentration levels (0.02, 0.05 and 0.5 mg/L). Average recoveries of Picoxystrobin (using each concentration three replicates) ranged 64.0~98.3% with relative standard deviations less than 10%, calibration solutions concentration in the range 0.1~5 mg/L, and limit of detection (LOD) and limit of quantification (LOQ) were 0.005 and 0.02 mg/L, respectively. The result showed that the developed analytical method is suitable for Picoxystrobin determination in agricultural products.

Simultaneous Analysis of 260 Pesticide Residues in Agricultural Products by Gas Chromatography/Triple Quadrupole Mass Spectrometry

A method for simultaneous analysis of about 260 pesticides by gas chromatography coupled to tandem mass spectrometry (GC/MS/MS) with a triple quadrupole analyzer (QqQ) has been studied. The pesticides were extracted with acetonitrile and cleaned up by a bilayer cartridge. A single injection method was developed for the monitoring of all of the targeted pesticides. Two MS/MS transitions were selected for each analyte using the intensity ratio obtained from them as a confirmatory parameter. By using matrix-matched standards, 260 pesticides could be determined in most matrixes with recoveries of 70-120% and a standard deviation of < or = 20 at 2 different fortification levels of 0.02 and 0.1 microg/g. The developed method was applied to the monitoring of 173 agricultural product samples from the local market. The sensitivities of this method were lower than with most of the selective GC detectors, such as flame photometric or single MS. The selectivity of QqQ gives a very clean chromatogram, making compound identification and confirmation easy. The quick and reliable monitoring was achieved by combination with rapid extraction and cleanup.

Development of Two Enzyme-Linked Immunosorbent Assays for Detection of Endosulfan Residues in Agricultural Products

Two competitive immunoassays, a laboratory assay based on microwell plates and a field test based on the use of polystyrene tubes, have been developed for the detection of endosulfan in agricultural products. The limit of detection for the microwell plate format was 0.8 +/- 0.1 microg/kg, and the limit of detection for the tube format was 1.6 +/- 0.2 microg/kg. A simple, rapid, and efficient extraction method was employed, and 76-112% recoveries of spiked samples were obtained. Methanol extracts of some agricultural product samples such as grape, carrot, spinach, and tobacco could be analyzed directly by immunoassay after dilution in 0.5% fish skin gelatin-phosphate buffered saline. In contrast, extracts of green tea caused significant interference in the assay, and a number of simple cleanup methods were ineffective in removing interference. However, use of the coagulating reagent polyvinyl pyrrolidone removed the matrix effect effectively. For the validation of the enzyme-linked immunosorbent assay (ELISA) tests, samples were analyzed by ELISA and gas chromatography (GC) after solid phase extraction. The relationship between data obtained using the tube assay and microwell assay was good (the lowest r(2) value was 0.94), and also, the immunoassay assay data correlated well with data obtained from GC analysis (the lowest r(2) value was 0.93). The developed immunoassay methods are the suitable methods for the rapid quantitative and reliable determination of endosulfan residues in agricultural products.