• Journal of Environmental Science International
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• v.4 no.3
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• pp.97-97
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• 1995

PCBs have been measured using GC-ECD, GC-MS, GC-ELCD, HPLC, TLC, NMR and Immunoassay. The analysis of PCBs using GC-ECD include the peak pattern method as none derivatization and the Perchlorination method as derivatization. This study was conducted to establish the perchlorination method with Sbcls from PCBs to decachlorinated biphenyl(DCB). The aroclor 1242 of PCBs was chlorinated and then, converted into the DCB which showed a single peak in GC-ECD chromatogram. The detection limit of DCB was 2pg. The quantification detection concentration of PCBs extracted with soxhlet was 0.5ng/g in the soil. PCBs were not detected in the suburban soil, but 174ng/g in the soil of industrial complex. Mean PCBs concentration of Shinchun stream at Kumho river and Jinchun stream at Nakdong river was calculated average 낙ngjg in 각e sediment. PCBs concentration in the sediment of Kumho river near 2-7km from conjunction with Nakdong river was average 154ng/g. PCBs concentration in the sediment of Nakdong river near conjunction with Kumho river was average 159ng/g.

• Journal of Environmental Science International
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• v.4 no.3
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• pp.249-258
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• 1995

PCBs have been measured using GC-ECD, GC-MS, GC-ELCD, HPLC, TLC, NMR and Immunoassay. The analysis of PCBs using GC-ECD include the peak pattern method as none derivatization and the Perchlorination method as derivatization. This study was conducted to establish the perchlorination method with Sbcls from PCBs to decachlorinated biphenyl(DCB). The aroclor 1242 of PCBs was chlorinated and then, converted into the DCB which showed a single peak in GC-ECD chromatogram. The detection limit of DCB was 2pg. The quantification detection concentration of PCBs extracted with soxhlet was 0.5ng/g in the soil. PCBs were not detected in the suburban soil, but 174ng/g in the soil of industrial complex. Mean PCBs concentration of Shinchun stream at Kumho river and Jinchun stream at Nakdong river was calculated average 낙ngjg in 각e sediment. PCBs concentration in the sediment of Kumho river near 2-7km from conjunction with Nakdong river was average 154ng/g. PCBs concentration in the sediment of Nakdong river near conjunction with Kumho river was average 159ng/g.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.238-245
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• 2011

This study was carried out to examine residual pesticides in dried agricultural products collected from Gyeonggi province in 2010. A total of 102 samples was collected and analyzed for 206 pesticides by multiresidue method using GC-${\mu}ECD$, GC-NPD, GC/TOF/MSD, HPLC-UVD, HPLC-FLD and HPLC/MS/MS. The detection rate of residual pesticides was 23.5% (24 of 102 samples) and the agricultural products exceeding their MRLs (Maximum Residue Limits) were 1 sample of pepper leaves. Additionally, the frequently detected pesticide were chlorothalonil, fenvalerate, chlorpyrifos, endosulfan, bifenthrin, cypermethrin, hexaconazole and iprodione. The pesticide types detected in the dried agricultural products showed in the descending order of organophosphorus (22%), pyrethroid (22%), organochloride (17%), dicarboxymide (11%), carboxymide (6%), carbamate (6%), triazole (5%) and the others (11%).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.3
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• pp.222-232
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• 2006

Objectives: The objective of this study was to propose the total isocyanate analytical method which involves derivation of 2,4-toluene diisocyanate(2,4-TDI), 2,6-toluene diisocyanate(2,6-TDI), 4,4'-methylenediphenyl diisocyanate(4,4'-MDI) and 1,6-hexamethylene diisocyanate(1,6-HDI) using 2-chlorobenzyl alcohol(2-CBA) or 2,4-dichlorobenzyl alcohol(2,4-DCBA), and analyzing of hydrolysate of the synthesized urethane with the gas chromatography(GC)/flame ionization detector(FID), GC/pulsed discharge ionization detector-electron capture detector(PD-ECD) and GC/mass selective detector(MSD). Methods: Urethanes were synthesized by reacting 2,4-TDI, 2,6-TDI, 4,4'-MDI and 1,6-HDI to 2-CBA or 2,4-DCBA. Urethanes was verified by TLC, HPLC/UVD and GC/MSD. For field application, the most suitable condition that 2-CBA coated in glass fiber filter removed completely and urethanes were not removed was searched. 2-CBA generated from hydrolysis of urethanes according to hydrolysis conditions. Diisocyanates were collected on field air and analyzed. Results: Urethanes which were white and solid phase synthesized by reacting 2,4-TDI, 2,6-TDI, 4,4'-MDI, 1,6-HDI and 2-CBA or 2,4-DCBA. And urethanes were verified by TLC, HPLC/UVD and GC/MSD. The most suitable conditions to remove 2-CBA coated in glass fiber filter were $87^{\circ}C$ and 20 mmHg and urethanes were not removed under same condition. Hydrolysis yields of urethanes were 99 % to 111 %. 2-CBA, the hydrolysate of urethanes was analyzed by GC/FID, GC/PD-ECD and GC/MSD. Conclusions: Simultaneous analysis of 2,4-TDI, 2,6-TDI, 4,4'-MDI and 1,6-HDI deriving with 2-CBA and 2,4-DCBA, along with a total isocyanate analysis, was feasible with GC/FID, GC/PD-ECD and GC/MSD. This result will be a guide of further study on total isocyanate analysis.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.271-282
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• 2013

This is the result of pesticide residue monitoring certified Good Agricultural Practice (GAP) by national agricultural cooperative federation (NACF) from 2009 to 2012. NACF evaluated simultaneously 283 pesticide multi-analysis method with GC (ECD, NPD) and HPLC. 6,590 agricultural products were analyzed in this period. As the results 1) detected 20.27% in 2009, 23.42% in 2010, 28.07% in 2011 and finally 31.75% in 2012, respectively. There was the total detected pesticide residue in the agricultural products. The violated ratio of agricultural products were 2.25% in 2009, 1.82% in 2010, 1.67% in 2011 and 3.47% in 2012, respectively. 13 pesticides went over the maximum residue limits (MRLs); carbendazim was the predominant violation. 40 pesticides; endosulfan was the predominant detected pesticide did not registered respectively crops in Korea. Most agricultural products that were under the MRLs met the safety standard, however agricultural products that contain neither registered nor set up MRL any level for example endosulfan in strawberry. Agricultural products that go over the MRLs with permitted pesticides, for example carbendazim in apple, are rejected. Because of these intricacies continual observation and evaluation will be need during GAP agricultural cultivation.

• Analytical Science and Technology
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• v.13 no.5
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• pp.630-635
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• 2000

The concentration of neurotransmitters in rat brain was determined by HPLC-ECD (electrochemical detection) method and the effects of methanol extracts of some crude drugs, such as Polygala Radix, Myristicae Semen, Zizyphi Semen, Acori graminei Rhizoma, Visci Herba, Liriopsis Tuber, Myrrha on the concentration of neurotransmitters in the ethanol-treated rat brain were investigated. By the administration of ethanol, dopamine (DA), 3, 4-dihydroxyphenyl acetic acid (DOPAC) and serotonin (5-HT) levels in frontal cortex and 5-HT level in hippocampus were significantly increased compared with the neurotransmitter levels in the brain of saline-treated rats. The ${\gamma}$-aminobutyric acid (GABA) level in frontal cortex was decreased by the same treatment. There was a tendency that the DA level in frontal cortex and striatum of ethanol-treated rats were increased by the administration of crude drug extracts. Especially, Myrrha and Visci Herba significantly increased the DA level of frontal cortex in ethanol-treated rats, while they significantly decreased the 5-HT level in the same region of the brain. GABA level in striatum of ethanol-treated rats was significantly decreased by Myristicae Semen, Visci Herba and Myrrha. These results suggest that the tested crude drug extracts have selective interaction with neurotransmitters in specified region of central nervous system.

• Journal of Radiation Industry
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• v.6 no.3
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• pp.205-209
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• 2012

The decomposition of 50 pesticides present in an aqueous solution using ${\gamma}-irradiation$ from a $^{60}Co$ gamma-ray source was investigated using laboratory-scale experiment. The rates of decomposition were determined using a gas chromatography-electron capture detector (GC-ECD), high-performance liquid chromatography-photo diode array detector (HPLC-PDA), and HPLC-fluorescence detector (FLD). When the initial concentration of pesticides was 10 ppm, and the radiation dose was 2, 5, 10, 20, and 30 kGy, respectively, 14 pesticide samples showed high removal rates (>50%) at absorbed doses of more than 10 kGy. With the exception of procymidone, they were all completely removed at a 30 kGy irradiation dose. These results provide fundamental data on the reactivity between gamma-irradiation and pesticides in an aqueous solution. Further, an evaluation of the toxicity of radiolytic intermediate products is required.

• Analytical Science and Technology
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• v.7 no.3
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• pp.395-402
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• 1994

Benomyl(Methyl-1-(Butyl Carbamoyl)-Benzimidazole-2-yl-Carbamate) is widely used as pre- and post-harvest pesticide. It converts into MBC(Carbendarzime:Benzimidazole-2-yl-carbamate) and butyl-isocyanate in mild condition. In this study, three analytical methods for MBC were compared in view of detectability, correctness, and sensitivity. The first and second are HPLC analytical method employing the UV detection of MBC. Our new third method was modification of PFBB(pentafluoro-benzylbromide) derivatization method with GC-ECD & MSD. The average recoveries and detection limit of MBC in the newly modified method are 95% and $0.001{\mu}g/g$ in whole bean and bean sprouts respectively. This new method prevent pesticide analysis from misdetecting in bean and bean sprouts.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.101-101
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• 1995

The effects of ginseng prepation, Adaptagen$\^$R/ (AD), on the central dopaminergic nervous system in the learning-impaired rats were studied. The learning impaired rats were rendered by the intracerebroventricular infusion of ethylcholine aziridium (AF64A), 3 nmol/each side. Three days after the infusion of AF64A, AD were orally intubated daily for five days, 200 mg/kg. The control groups were intubated with distilled water. Twenty four hours after the last intubation, The changes in the specific bindings of dopamine receptors, the concentrations of dopamine (DA) and metabolites, The activities of tyrosine hydrosylase (TH) and monoamine oxidase (MAO) were analyzed using receptor radiography, HPLC-ECD and the methods in enzyme-assays, respectively.

• YAKHAK HOEJI
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• v.32 no.1
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• pp.50-54
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• 1988

A simple and sensitive method was studied for the simultaneous determination of catecholamine, indoleamine and their related metabolites by high performance liquid chromatography with electrochemical detector. Norepinephrine, dopamine, serotonin and their metabolites of 3,4-dihydroxyphenylacetic acid, homovanillic acid, 5-indoleacetic acid were resolved from rat brain tissue homogenates by separation on reversed phase $C_{18}$ column with mobile phase consisting of monochloroacetate buffer (pH2.47), 1.42mM sodium octyl sulfonate and 7% acetonitrile. Both catechols and indoles can be eluted in 15min. The sensitivities of this method are sufficient for determination of at least 100 pg of neurochemical amines in brain samples, for example, frontal cortex, olfactory bulb, striatum, septum, hippocampus, thalamus, hypothalamus, medulla & pons and cerebellum. The highest level of dopamine was observed in striatum whereas norepinephrine and serotonin were in hypothalamus.