• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1009-1014
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• 2000

In order to detect pantothenic acid (PA), conditions for enzyme-linked immunosorbent assay (ELISA) were established. Anti-PA-BSA antibody was produced from rabbits immunized with PA-bovine serum albumin (BSA) conjugates which were prepared by the bromoacetyl chloride [Bc] method (PA-BSA[Bc]) and by the periodate oxidation [Po] method (PA-BSA[Po]). PA-BSA[Bc] and PA-BSA[Po] was used as a coating antigen for competitive indirect(ci)ELISA. The Anti-PA-BSA[Po] antibody on ciELISA showed no competitive reaction. The detection limit of PA by ciELISA using Anti-PA-BSA[Bc] antibody was 1 ppm. The Anti-PA-BSA[Bc] antibody showed little cross-reactivity to PA derivatives such as pantoyllactone, pantetheine, pantothenyl alcohol, and acetyl CoA. The detection limit of PA by microbiological assay (MBA) was 10 ppb. Assay recoveries of PA in egg, cow's liver, and lettuce by ciELISA were 109, 64, and 344%, respectively, comparing with the MBA results.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.548-553
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• 2000

Two drug-enzyme conjugates of dexamethasone-subtilisin and dexamethasone-cellulase have been synthesized and characterized to study their drug-protein incorporation ratio, immunoreactivity, enzyme activity and stability and these studies proved that a variety of drug enzyme conjugates could also be synthesized and characterized.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s01
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• pp.40-47
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• 1989

In spite of the development of highly sophisticated instrument, the precise quantitation of plant hormones still has many difficulties. Due to their high specificity, sensitivity and minimal sample purification steps, immunological assays have been widely applied for plant hormone assay. Enzme-linked immunosorbent assay technique for the determination of plant hormones was developed by Voller in 1978. Immunological assays are accomplished by competition of labeled tracer antigen and unlabeled antigen for a limited number of specific antibodies. The use of enzyme as replacement labels for radioisotopes enabled much of the sensitivity and specificity of radioimmunoassay (RIA) to be retained but without the inherent disadvantage of high capital cost, potential health hazard, and short shelf life of the labeled reactants.

• Toxicological Research
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• v.17
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• pp.197-199
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• 2001

Enhancement of antigen-specific IgE is a hallmark of allergic hyperresponsiveness, therefore it is necessary to adopt or develop a highly sensitive and specific assay for determination of allergen-specific IgE levels in vivo. In this presentation, we introduce an ELISA (enzyme linked immunosorbent assay) system developed to measure the levels of chicken egg ovalbumin (OVA)-specific IgE in serum. The ELISA method uses a commercially available purified rat anti-mouse IgE as a capture Ab and biotinylated OVA as a detection reagent. Avidin-peroxidase with its substrate is used for color development resulting in optical density measurement at 405 nm. The ELISA system produces a highly sensitive dose-response relation-ship between optical density levels and the dilution titer of the OVA-IgE standard serum but no cross-reaction with unrelated IgE or IgG. It is believed that the system is an Efficient tool to delineate an adjuvant effect of environmental pollutants on development of asthmatic and atopic responses.

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.599-603
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• 2002

A selective enzyme-linked immunosorbent assay (ELISA) for the insecticide isofenphos was developed. Three different analogues (haptens) of isofenphos were synthesized and were coupled to carrier proteins through the pesticide thiophosphate group t o use as immunogens or coating antigens. Rabbits were immunized with one of the haptens coupled to BSA for production of polyclonal antibodies and the sera were screened against each of the other two haptens coupled to ovalbumin (OVA). Using the sera of highest specificity, an antigen-coated ELISA was developed, which showed an I50 of 96 ng/mL with the detection limit of 2 ng/mL. The antibodies showed negligible cross-reactivity with other organophosphorus pesticides and the phenol metabolite of isofenphos, which makes the developed assay suitable for the selective detection of isofenphos. An antibody-coated ELISA was also developed, which showed an I50 of 580 ng/mL with a detection limit of 70 ng/mL.

• Biomedical Science Letters
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• v.8 no.4
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• pp.235-244
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• 2002

This study was carried out to determine the blood and milk progesterone by enzyme-linked immunosorbent assay (ELISA), and milk urea nitrogen (MUN) in cows. MUN and protein concentration were determined using automated infared procedures. The optimum conditions of ELISA system was investigated including the first and second antibody titres, bound percent, and enzyme conjugate and also the factors on MUN and protein concentration by sampling procedures and addition of preservatives. Progesterone antibodies did not react to pregnenlone, testosterone, estrone, estradiol-l7$\beta$, aldosterone, cortisol, corticosterone and 11$\alpha$-dehydroxycortisone (DOC), but reacted with only progesterone. The intra and inter-assay coefficient of variation 4.5%, 6.1~9.4% when used of bovine serum. The morning, MUN concentration (17.6$\pm$2.8 mg/100 ml) in the 13 herds was similar to that of evening MUN concentration of the lactating cows from the same herd. A significant relationship between morning and evening milk samples of upper parameters was found r=0.93. Difference in MUN concentration with sampling procedures and using of preservatives were investigated.

• Korean Journal of Veterinary Research
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• v.33 no.3
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• pp.539-545
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• 1993

This study was carried out the determine the progesterone concentration for serum by enzyme-linked immunosorbent assay(ELISA) in bovine adult at estrous, pregnant, after patuation and male, female calves of 1 month old, respectively. The results obtained were summarized as follows ; 1. The assay has a sesitivity of $0.1ng/m{\ell}$. 2. Intra and inter-assay coefficient of variation were 4.5%, 6.1~9.4% when used for the determination of progesterone in samples of bovine serum. 3. The percentages of recovery for progesterone added were between 88.0 to 88.9%. 4. Progesterone concentration of adult bovine serum at estrus, pregnant and after 1 day of parturition were $0.37{\pm}0.16$, $7.1{\pm}1.0$, $0.13{\pm}0.02ng/m{\ell}$, respectively. 5. There was no differences in serum progesterone concentration of calves both male($0.16{\pm}0.03ng/m{\ell}$) and female($0.15{\pm}0.04ng/m{\ell}$) on 1 month old. From these results, progesterone determination by ELISA is very applicable to detect of early pregnancy diagnosis, factorial analysis of reproductive disorder, and also reproductive physiological functions such as veterinary therapeutic measures and monitoring of cyclicity.

• Infection and chemotherapy
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• v.50 no.4
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• pp.311-318
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• 2018

Background: Zoster vaccination is recommended for people with a history of herpes zoster (HZ), but the most effective timing of vaccine administration after zoster illness is unresolved. This prospective observational study compared the immunogenicity and safety of administering HZ vaccine at 6-12 months and 1-5 years after zoster illness. Materials and Methods: Blood samples were collected before the administration of live zoster vaccine and 6 weeks after vaccination. Varicella-zoster virus (VZV) IgG concentrations and T-cell responses were assessed by glycoprotein enzyme-linked immunosorbent assay and interferon-${\gamma}$ enzyme-linked immunospot assay (ELISPOT), respectively. Results: The baseline geometric mean value (GMV) of VZV IgG was higher in the 6-12 months group than in the 1-5 years group (245.5 IU/mL vs. 125.9 IU/mL; P = 0.021). However, the GMV increased significantly in both groups (P = 0.002 in the 6-12 months group; P <0.001 in the 1-5 years group). The results of the ELISPOT assay were not significant for differences of the GMV between baseline and 6-week post-vaccination groups, while the GMV increased significantly in both groups (P = 0.001 in the 6-12 months group; P <0.001 in the 1-5 years group). Conclusion: The immunogenicity of zoster vaccine may be similar whether administered 6-12 months, or >1 year after zoster illness. Trial Registration: ClinicalTrials.gov Identifier: NCT02704572

• Journal of Food Hygiene and Safety
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• v.9 no.3
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• pp.123-131
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• 1994

An enzyme-linked immunosorbent assay(ELISA) was developed for the detection of residual gentamicin(GM) in edible animal products. The immunogen(GM-KLH conjugate) and coating antigen(GM-BSA conjugate) were prepared by coupling GM sulfate to keyhole limpet hemocyanin(KLH) and bovine serum albumin(BSA) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, respectively. Polyclonal antibody to GM was produced in rabbits(New Zealand White, female) by using the immunogen and the antibody titer was measured by indirect ELISA. A competitive ELISA was developed using GM-bovine serum albumin conjugate as a coating antigen, GM(as standards or sample), polyclonal antibody to GM, secondary antibody conjugated with horseradish peroxidase as an enzyme, and H2O2 and o-phenylenediamine dihydrochloride as a substrate and a chromophore, respectively. The detection limit of GM was 10 ng/ml and the standard curve of GM(n=26) was linear up to 10 $\mu\textrm{g}$/ml in this competitive ELISA system. There were no cross-reactivities of the partially purified antibody between GM and the various antibiotice such as amikacin, benzyl-penicillin, chloramphenicol, erythromycin, furazlidone, kanamycin, neomycin, oleandomycin, streptomycin, sulfathiazole and thiamphenicol(CR50<0.05%)

• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.503-515
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• 1989

Critical parameters affecting sensitivity and specificity of an enzyme-linked immunosorbent assay(ELISA) for detection of antibodies to avian infections bronchitis virus(IBV) were standardized. By adopting the optimized conditions an equation calculating ELISA antibody titers from the observations at single serum dilution was formulated. The purified antigen of IBV Mass-41 strain was dispensed into polystyrene microplate wells at a concentration of 300ng per well($100{\mu}l$) and the plates were coated by completey drying at $37^{\circ}C$. Diluted chicken serum and horseradish peroxidase conjugated goat anti-chicken IgG were added in order in $100{\mu}l$ volumes per well and allowed to react for 30 minutes each at room temperature. Just before use and after each reaction the plates were washed three times with distilled water. Finally o-phenylenediamine solution was added as an enzyme substrate. After incubation for another 15 minutes at room temperature absorbances were read at 492nm. Hyperimmune serum against Mass-41 strain was used as internal reference positive(IRP) serum. After repeated titration of IRP and negative serum, a constant titer of IRP was determined. Serum titrations were carried out for various sample sera together with IRP and negative sera and the observed titers of sample sera were corrected by reflecting the ratio between observed and constant titers of IRP serum. These corrected titers of the sample sera were plotted against sample/positive(S/P) OD ratios. All the OD's measured in the serum titrations were also corrected by substracting negative serum OD. The following equation was formulated from the above data; $Log_{10}$ ELISA titer=$5.568({\log}_{10}S/P)+4.161$ Thus it was possible to calculate ELISA titer by measuring absorbance at 1/400 single serum dilution. Titer measured by cross ELISA tests employing Mass-41 strain and three local IBV isolates were similar. These results suggest that the ELISA tests standardized in this study can be used for evaluating not only vaccinal immunity but also for infection status against fields IBV's.