• Food Science and Biotechnology
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• 제15권6호
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• pp.959-966
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• 2006

The electron-capture detector (ECD) of gas chromatographs (GC) has been used widely in pesticide analysis. However, as ECD relies on radioactive material, it is troublesome to purchase and maintain. Therefore, potent replacements for ECD were investigated. A Pulsed-discharge detector (PDD) for ECD was tested and the analytical results of PDD (ECD mode), ${\mu}ECD$, and nitrogen-phosphorus detector (NPD) were compared for 107 pesticides including organochroline, organophosphorus, pyrethroids etc. The number of pesticides identified at the lowest limit of detection (LOD) was 36, 29, and 2 for PDD, ${\mu}ECD$, and NPD, respectively. The remaining pesticides showed same response to PDD and ${\mu}ECD$. The GC-PDD analysis of pesticides spiked into representative agricultural products (brown rice, spinach, and mandarin oranges) also showed good and/or equivalent recoveries using $GC-{\mu}ECD$.

• 한국환경과학회지
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• 제6권4호
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• pp.385-389
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• 1997

농약 잔류물을 70% acetone으로 추출한 다음 dichloromethane 층으로 옮겨 추출물을 florisil과 alumina-N으로 충진시켜 column chromatography를 행하였다. 마지막 추출물을 electron-capture detector(GC/ECD)와 nitrogen-phosphorus detector(GC/NPD)를 가진 GC로 분석하였다. 분석 결과 17 가지의 유기염소계 농약과 15 가지의 유기인계 농약의 회수율이 각각 60.8 에서 84.9%와 70.5에서 100.0%의 범위이었으며(phosmet와 azlnphos-methyl은 제외) 본 분석 방법의 최소 검출 준위도 낮았다(0.021-0.058mg/kg).

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.199-201
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• 2005

This paper describes a simple procedure for the quantitative analysis of 7 PCBs (polychlorinated biphenyls) in soils on the waste reclaimed land, The procedure involved sample clean up using silicagel column, acetonitrile partition and sulfuric acid procedures. The instrumental technique is applied GC/PDD(gas chromatography/pulsed discharge detector) and GC/ECD(gas chromatography/electron capture detector). Concentration of $sub-{\mu}g/g$ level was attainable with 20g soils on the waste reclaimed land.

• 분석과학
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• 제12권5호
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• pp.408-414
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• 1999

기체 크로마토그래피-전자포획검출기 (gas chromatograph-electron capture detector : GC-ECD)를 이용하여 사람의 혈액 내에 존재하는 homocysteine (Hcy), 관련 화합물인 cysteine (Cys)과 methionine (Met)에 대해 선택적이고 감도 좋은 분석방법에 대하여 연구하였다. 시료는 혈장 내에서 환원과정을 거친 후 ethyl chloroformate (ECF)와 pentafluoropropyl alcohol (PEP-OH) 유도체화 시약을 사용하여 N(O,S)-ethylearhonyl pentafluoropropyl (PEP) ester 유도체를 만들어 추출의 효율을 높이면서 동시에 GC-ECD에 대한 크로마토그래피 성질을 향상시켰다. 생성된 유도체들은 chloroform으로 추출한 후 잔류물을 완전히 건조시키고 hexane으로 추출하여 GC-ECD로 분석하였다. Hcy와 Met는 $5-50{\mu}mol/L$, Cys는 $40-400{\mu}mol/L$ 범위에서 $R^2=0.990$ 이상의 직선상의 상관관계를 나타내었다. 이 작성한 질량곡선을 통해서 5명의 자원자들의 혈액 중에 존재하는 Hcy, Cys, met의 함량을 분석하였다.

• 한국식품위생안전성학회지
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• 제16권1호
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• pp.61-65
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• 2001

Electron capture deteotor가 장착된 gas chromatography를 이용하여 간장에서 3-monochloro-1, 2-propanediol(MCPD)의 효율적인 분석조건을 조사하였다. MCPD를 직접 분석하는 것 보다 MCPD를 phenylboric acid로 유도체화하여 분석하는 경우가 sharp한 peak를 얻을 수 있었으며, 감도도 우수하였다. 유도체화 방법을 실온에서 5분간 vortex혹은 9$0^{\circ}C$에서 20분 반응시켜 분석한 결과, R값이 각각 0.9997과 0.9977로 큰 차이를 보이지는 않았다. MCPD의 추출방법은 Extrelut 3 column을 사용하는 것이 ethyl acetate로 직접 추출하는 것보다 회수율이 월등히 높았으며, MCPD의 농노가 높을수록 회수율이 낮게 나타났다. 하지만 MCPD를 정성적으로 분석하고자 할 경우 ethyl acetate로 직접 추출하는 방법도 유효한 것으로 나타났다. 간장에 MCPD를 spiking 하고 gas chromatography-electron capture detector 및 gas chromatography-mass selective detector로 분석한 결과 sharp한 모양의 peak를 얻을 수 있었으며, mass spectrum으로 MCPD를 확인할 수 있었다.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1997년도 가을 학술발표회 프로그램
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• pp.37-39
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• 1997

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 organophosphorus 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 mg/kg).

• 한국환경보건학회지
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• 제27권1호
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• pp.88-92
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• 2001

The simultaneous analytical method for 37 residual pesticides was developed by a gas chromatography with $^{63}$ Ni electron capture detector. Pesticides added in soybean sample were extracted with 70% acetone in water and methylene chloride in oder, and then cleaned up via open-column apparatus packed with florisil and alumina N. The Ultra-2 fused capillary column was used to separate the products. The resolution between the last isomeric peak of cypermethrin (56.398 min) and the first isomeric peak of flucythrinate (56.421 min) was not satisfactory and the last isomeric peak of fenvalerate(58.783 min) and the first isomeric peak of fluvalinate(58.835 min) was overlapped. Except for $\alpha$-BHC, dichlofluanid, captan, and captafol, most recoveries were showed over 70%.

• Archives of Pharmacal Research
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• 제15권2호
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• pp.109-114
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• 1992

For the risk assessment of human exposure to volatile halogenated hydrocarbons, a dynamic purge trap/on-column cryofocusing method using capillary gas chromatograph-$^{63}Ni$ electron capture detector and thermal desorption unit was applied to analyze the free forms, metabolites of 1, 1, 2-trichloroethylene and 1, 1, 2, 2-tetrachloroethylene. The urine sample was diluted with distilled water, hydrolyzed and sealed. Then the inert gas was infused to purge out free 1, 1, 2-trichloroethylene, free 1, 1, 2, 2-tetrachloroethylene and urichloroethanol. These compounds were trapped to $Tenax^R$ / GC-gas trap device throughout clean up tube. Being undertectable to gas chromatograph directly, trichloroacetic acid was methyl esterificated and trapped in the manner above mentioned. The optimal incubation time to get best recovery of methyl ester was 4 hours at $60^circ$C. The concentrations of free volatile halogenated hydrocarbons and their metabolites in urine were obtained of free volatile halogenated hydrocarbons and their metabolites in urine were obtained from 5 healthy volunteers. This analytical method is expected to make the biological monitoring more precise and convenient.

• 분석과학
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• 제19권2호
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• pp.155-162
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• 2006

본 연구에서는 잔류농약을 효과적으로 제거하는 방법을 토양 및 수용액상에서 연구하였다. 이를 위해 표준물질은 유기염소계 ${\alpha}$-endosulfan, ${\beta}$-endosulfan을 사용하였다. 분석방법은 각각 채취한 시료를 전처리하여 Ultra II[$(30m{\times}0.25mm(ID){\times}0.25{\mu}m$] 컬럼을 장착한 GC-${\mu}$-electron capture detector(${\mu}$-ECD)로 분석하였다. 토양 중 잔류농약의 회수율은 96-100%로 나타났다. 토양에 농약분해제를 살포하여 시간별 ${\alpha}$-endosulfan, ${\beta}$-endosulfan의 변화량을 분석한 결과 73, 61% 감소하였다. 토양시료에 농약분해제를 첨가하고, 수분의 양을 10 mL에서 100 mL로 증가 시키면서, 잔류농약의 변화량을 측정하였다. 그 결과, ${\alpha}$-endosulfan은 45%에서 85 %로, ${\beta}$-endosulfan은 44%에서 88%로 제거되었다. 마지막으로, 수용액상에서도 시간별 endosulfan의 제거율 실험을 하였다. 실험 결과 30분 내에서 ${\alpha}$-endosulfan은 99%, ${\beta}$-endosulfan은 98%가 분해 제거되었다. 이와 같은 현상은 농약분해제에 많은 유기산염과 강알칼리 성분들이 알칼리 가수분해를 일으킨 것으로 추정할 수 있다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.238-252
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• 2002

In order to screen out indicators for the discrimination of ginseng habitat, some physical and chemical characteristics of Korean red ginsengs (94 kinds) and Chinese red ginsengs (50 kinds) were analyzed by using a rheometer, an electronic nose system, a combined technique of solid phase micro-extraction (SPME) and gas chromatograph equipped with an electron capture detector (GC/ECD), an X-ray fluorescence spectrometer (XRF), an inductively coupled plasma mass spectrometer (ICP/MS), a near infrared spectrometer (NIRs) and high performance liquid chromatography equipped with evaporative light scattering detector (HPLC/ELSD). The results are summarized as follows: (i) The rhizome strengths of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. (ii) The electronic nose patterns of Korean red ginsengs were significantly different from those of Chinese red ginsengs. (iii) Some unidentified peaks were detected not in the headspace of Korean red ginsengs but in the headspace of Chinese red ginsengs when the headspace volatiles prepared by the SPME technique were analyzed by GC/ECD. (iv) Either the content ratios of K to Ca or Mn to Fe were significantly different between Korean red ginsengs and Chinese red ginsengs. (v) The reflectance ratios of NIRs wavenumbers such as $904\;cm^{-1}\;to\;1088\;cm^{-1}$ for Korean red ginsengs were significantly different from those for Chinese red ginsengs. (vi) The content ratios of ginsenoside-Rg to ginsenoside-Re of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. These results indicate that the rhizome strength, the electronic nose pattern, the occurrence of ECD-sensitive headspace volatile components, the content ratios of K to Ca and Mn to Fe, the NIRs pattern and the content ratio of ginsenoside-Rg to -Re may be indicators for the discrimination of ginseng habitat.