• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1399-1426
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• 2002

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of the organophosphorus insecticide bromophos. Three bromophos analogues (haptens) were synthesized and were coupled to carrier proteins to use as immunogens or coating antigens. Rabbits were immunized with either one of two haptens coupled to bovine serum albumin (BSA) for production of polyclonal antibodies, and the sera were screened against one of the haptens coupled to ovalbumin (OVA). Using the serum with highest specificity and an enzyme tracer, an antibody-coated ELISA was developed, which showed an $IC_{50}$ of 40 ng/mL with a detection limit of 7 ng/mL. The antibodies in this assay showed negligible cross-reactivity with other organophosphorus pesticides except with the insecticides chlorpyrifos and fenitrothion.

• Journal of Yeungnam Medical Science
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• v.15 no.1
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• pp.143-150
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• 1998

The aim of this study was to evaluate domestic enzyme immunoassay(EIA) kit 'LG RCD 3.0' (LG) for the detection of antibody to hepatitis C virus(anti-HCV) in comparision with Axsym HCV version 3.0(Axsym), Cobas Core anti-HCV EIA(Cobas). Cobas kit shows better clear distinction between positive and negative by signal/cutoff ratio(S/C), but it also reveal relatively high false positive rate. The concordance rate of test results between LG and Axsym was 96.2%, between LG and Cobas was 95.5%, and total agreement between three EIA kit was 93.9%. LG were relative poor distinction between positive and negative results, but it could be applied clinically as a screening tool for hepatitis C in general population. The SIC of one false negative result by LG was 0.91, and false positive were less than 4.0, therefore we concluded it is necessary to confirm by immunoblotting assay when SIC were between 0.8 and 4.0.

• Proceedings of the Ginseng society Conference
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• 1998.05a
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• pp.32-32
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• 1998

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.270.1-270.1
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• 2003

Enzyme-linked immunoassay system using monoclonal antibody (MAb) has become an important methodology for the quantitative and qualitative analysis of drugs and phytochemical compounds having small molecular weight. In this study, monoclonal antibodies against berberine, one of main constituent of Phellodendron amurense, Coptis japonica and Corydalis turtschaninovii, were produced. (omitted)

• Journal of Biosystems Engineering
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• v.31 no.6 s.119
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• pp.535-540
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• 2006

For a biosensor development, an enzyme-linked immunosorbent assay (ELISA) of the fungicide iprovalicarb was developed by minimizing the processing time. The time for whole incubation process was reduced from 135 minutes to 15 minutes. The concentration of antibody was varied to improve sensitivity. The total processing time was reduced from 2.5 hours to 20 minutes, the final sensitivity ($IC_{50}$ value) of 7.93 ng/mL and the lowest detection limit of 0.045 ng/mL were obtained. This ELISA was applied to potatoes and onions, and the recoveries were in the range of 98.85 $\sim$ 101.20% and 87.97 $\sim$ 102.70%, respectively. Accordingly, this method can be used as basis for a biosensor for rapid monitoring of iprovalicarb residues in crops.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.681-684
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• 2007

An immunoassay method was developed to quantitatively detect phosphinothricin-N-acetyltransferase (PAT) encoded by the Bialaphos resistance (bar) gene in genetically modified (GM) pepper. The histidine-tagged PAT was overexpressed in Escherichia coli M15 (pQE3l-bar) and efficiently purified by $Ni^{2+}$ affinity chromatography. A developed sandwich enzyme-linked immunosorbent assay (S-ELISA) method (detection limit: $0.01{\mu}g/ml$) was 100-fold more sensitive than a competitive indirect ELISA (CI-ELISA) method or Western blot analysis in detecting the recombinant PAT. In real sample tests, PAT in genetically modified herbicide-tolerant (GMHT) peppers was successfully quantified [$4.9{\pm}0.4{\mu}g/g$ of sample (n=6)] by the S-ELISA method. The S-ELISA method developed here could be applied to other GMHT crops and vegetables producing PAT.

• Korean Journal of Animal Reproduction
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• v.14 no.3
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• pp.165-173
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• 1990

A simple and sensitive microplate enzyme immunoassay(ELISA) was developed for progesterone, based on progesterone monoclonal antibody as anti-progesterone, horseradish peroxise(HRP) as enzyme-label and tetramethylbenzidine(TMB) as substrate. The assay has a sensitivity of 5pg-120pg/well and intra- and inter assay coefficients of variation for progesterone standard curve(0.1ng-3.2ng/ml) were ranged 4.4-10.6% and 5.-12.6%, respectively. They assay is performed in less than two hours and provide reliable values to differentiate among samples from day 0(A.I.), day 14 and day 19. The discriminatory levels for early pregnancy diagnosis are [>10ng(day 19) & decreasing rate <1.5 : pregnancy] and [ 7ng & decreasing rate 1.5 : non-pregnancy]. The accuracy of the pregnancy diagnosis for cows classified as positive(pregnancy) and negative(non-pregnancy) were 96% and 100%, respectively.

• Journal of Biosystems Engineering
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• v.28 no.6
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• pp.505-510
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• 2003

In Korea, due to its broad efficacy as a systemic insecticide, imidacloprid has been widely used in rice paddies to control sucking insects, soil insects, and some chewing insects and in apple orchards to control various insects pests. To quantify the imidacloprid residue concentrations, samples are assayed in vitro using enzyme-linked immunosorbent assays(ELISA). These assays generally require several hours to perform. As a biosensor, a competitive imidacloprid ELISA was modified to measure insecticide concentrations. It was found that a total assay time of 15 min(10-min antibody-antigen binding, and 5-min substrate development) is sufficient for monitoring imidacloprid concentrations. Further work is needed to improve the sensitivity of the measurement protocol.

• Korean Journal of Animal Reproduction
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• v.17 no.4
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• pp.347-356
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• 1994

A simpled and sensitive microplate enzyme immunoassay(EIA) was developed for the determination of progesterone concentration in serum, based on progesterone monoclonal antibody as anti-progesterone, horseradish peroxidase(HRP) as enzyme-label and tetramethylbenzidine(TMB) as substrate. The assay has a sensitivity of 5 pg-120pg/well and intra- and inter-assay coefficients of variation for progesterone standard curve (1.0ng~10.0ng/ml) were ranged 2.5~9.9% and 1.7.8.0%, respectively, determination coefficient of the regressio equation of our standard curve(R2=0.990$\pm$0.007) were high, and this is the same level as that of commercial kit(Hormonost Bio-Lab, Germany, R2=0.98~0.99). The progesterone concentration of serum determined by both kits (Work & Bio-Lab) were significantly correlated (r=0.95, P<0.01) although a little higher value were resulted in our kit than that of commercial kit. It generally is these results indicated that the microplate-EIA can be cused for the determination of progesterone in serum, as well as, for the determination of the early pregnancy diagnosis.

• The Korean Journal of Zoology
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• v.36 no.4
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• pp.522-528
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• 1993

Monoclonal antibodies (MAbs) against human alpha-fetoprotein (AFPI was produced by hybridizing SP 210-Ag 14 mouse myeloma cells with spleen cells of Balb/c mice immunized with purified AFP. Two subclones (D-6 and I-6) were expanded as ascite tumors in svngenic mice, and from ascitic fluid immunoglbulins were Pruified. Each anibodv was identified to be homogeneous by several criteria, and the affinity constant of D-6 and I-6 MAb to AEP was calculated to be 4.2${\times}$10-8 and 6.4${\times}$10-8 M-1, respectively. With these MAbs sensitive and accurate enzyme linked immunosorbent assay method was established.