본 연구는 불법적으로 수산물에 사용될 수 있는 염료 18종에 대한 안전관리 강화를 위해 정량 및 정성 분석이 가능한 LC-MS/MS를 적용하여 검증하기 위해 수행되었다 . 확립된 시험법은 CODEX CAC/GL-71 가이드라인에 따라 직선성, 정밀성 , 정량한계 및 회수율 등을 통해 유효성을 확인하였다 . 대상시료에 1% 아세트산을 함유한 아세토니트릴로 추출 후 C18 과 PSA로 정제하였다 . 본 실험에서 정량한계는 0.002 mg/kg 수준으로 정량한계를 포함한 농도에 따라 검량선을 작성하였고 모두 0.98 이상의 직선성을 확인하였다 . 또한 정확성은 63%-112% 이고, 정밀도는 15% 이하로 재현성이 우수하였다 . 국내 유통 중인 수산물 124 건을 수거하여 개발된 분석법의 적용성 검증과 안전성을 확인하고자 잔류실태조사를 실시 하였고 그 결과 7건이 미량으로 검출 되었고 부적합은 없었다 . 확립된 시험법은 수산물 안전관리에 활용할 수 있을 것으로 사료되는 바이다 .
A simple and fast analytical method based on liquid chromatography-tandem mass spectrometry was developed for detection of the veterinary drugs acetanilide, anthranilic acid, antipyrine, cyproheptadine, diphenhydramine, DLmethylephedrine, and phenacetin in bovine milk. The target analytes were extracted from milk samples by using acetonitrile followed by clean-up with C18 and liquid-liquid purification with saturated n-hexane. A reverse-phase analytical column was employed with a mobile phase comprising (A) 0.1% formic acid in distilled water and (B) 0.1% formic acid in acetonitrile to achieve the best chromatographic separation. Matrix-matched calibration curves (r2 ≥ 0.9986) were constructed using six concentrations (1, 2, 5, 10, 20, and 40 μg/kg) of drugs in the milk matrix. Recoveries at three drug-spiking levels (5, 10, and 20 μg/kg) ranged from 71.2% to 103.8% with intra-day and inter-day relative standard deviation (RSD) values of ≤ 8.6%. The calculated limits of quantification (LOQ) were 0.19-7.1 μg/kg.
A simple, selective and sensitive procedure for the confirmation of 14 sulfonamide antibacterials in milk was developed. The milk samples were homogenized, extracted and deproteinized by acetonitrile and defatted by n-hexane. Analysis was performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) in positive mode for all 14 analytes. Mass spectral acquisition was performed in the multi reaction monitoring mode (MRM), selecting two structurally significant transitions per compound. The calibrations were performed in sample matrixes and the interference effect of sample matrixes on the ionization was effectively eliminated. Good linear relationship (R2=0.992~ 0.999) were observed at 6 concentrations of 2.5~100 ng/g. Satisfied recoveries (86.3~110.2%) of all sulfonamides were demonstrated in spiked milk at three levels from 5 to 20 ng/g. The limits of quantitation (LOQs) for sulfonamides ranged from 0.25~2.1 ng/g.
This study was carried out with the detection for multiresidue of the carbamate pesticide such as carbaryl and cabofuran by enzyme-inhibition method. The check time for determination of acetylcholinesterase(AChE) activity was selected at 60 sec. The AChE activity in chicken brain determined by the Ellman's method was 162 μmol/min/g protein. I50 for AChE by carbamate pesticide with wet kit was 0.169 mg/L of carbaryl and 0.089 mg/L of cabofuran, respectively. The incubation time for enzyme kit with substrate kit was 30min for determination of AChE activity. Enzyme kit with substrate kit was stable at 4oC and 25℃ for 5 days. Limit detection concentration of carbaryl with dry kit for AChE was 0.05 mg/L. The dry kit such as wet kit applied Enzyme-Inhibition(EI) method with AChE was confirmed the multiresidue method to detect the carbamate pesticides.
Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC/ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pesticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azinphos-methyl). The minimum detectable levels of this analytical method were low(0.021-0.058㎎/㎏).
Organophosphate pesticides were extracted with 70% acetone and then transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil The final extract was analyzed by gas chromatography with nitrogen-phosphorus detector(GC/NPD). Recoveries of the 18 organophosphate pesticides were ranged from 88.7% to 100.0% for the narrow-bore capillary GC(Ultra-2). The minimum detectable level of this analytical method was 0.019 - 0.035 ㎎/㎏. Sample throughput(extraction, open-column chromatography, and GC analysis) was decreased considerably (8h per sample).