• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.522-525
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• 2011

In this study, an established enzyme-linked immunosorbent assay and immuno-chromatography technique are combined to fabricate an immuno-strip sensor for the detection of S. aureus. The immuno-strip is manufactured by using four different functional membranes. The capture antibody is immobilized on the nitrocellulose membrane due to the high affinity and the capillary action through porous membranes induces a flow of sample. A colorimetric signal is appeared according to the enzyme reaction and is analyzed by the digital camera (qualitative analysis) and home-made image analysis software (quantitative analysis). Under the optimal conditions, samples with S. aureus in the range of $2.7{\times}10^4{\sim}2.7{\times}10^7CFU/mL$ can be detected by the colorimetric method within 30 min.

• 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.

• 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.57 no.1
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• pp.31-36
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• 2017

Japanese encephalitis (JE) is an important zoonosis caused by the mosquito-transmitted JE virus (JEV), which is a causative agent of reproductive failure in pregnant sows. Detection of JEV antibodies in swine is performed by hemagglutination inhibition (HI), virus neutralization (VN), and the plaque reduction neutralization test (PRNT). The most stringent PRNT is the 90% endpoint PRNT ($PRNT_{90}$). These conventional assays are difficult to carry out in diagnostic laboratories with insufficient instruments or cell culture systems. An alternative assay that is easily conducted and time efficient is required. In this study, we improved the indirect enzyme-linked immunosorbent assay (I-ELISA) with clarified antigen for the detection of JEV antibodies. The I-ELISA results obtained from 175 swine serum samples were compared with HI, VN, and $PRNT_{90}$ results. The sensitivity of I-ELISA was 91.8%, 95.0%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. The specificity of I-ELISA was 92.2%, 94.7%, and 94.7% compared with HI, VN, and $PRNT_{90}$ results, respectively. Moreover, the I-ELISA results were significantly correlated with the HI (r = 0.93), VN (r = 0.95), and $PRNT_{90}$ (r = 0.92) results. These results suggest that the improved I-ELISA is useful for serosurveillance of JEV in swine.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.613-618
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• 1997

Direct competitive enzyme linked immunosorbent assay(ELISA) with monoclonal antibodies have been studied for quantitative determination of T-2 toxin from the mold corn. The T-2HS, T-2HS-BSA, T-2HS-HRP and monoclonal antibodies against T-2 toxin produced in the studies were qualified for quantitative ELISA test of T-2 toxin. The mean recovery rate from ground com spiked T-2 toxin was 83%. The meaning range of the T-2 test was 60ng to $2{\mu}g$. According to the recovery results with the com spiked T-2, the tests proved to be suitable in the screening of the moldy feed samples for the presence of T-2 toxin and will be able to become the basis of the ELISA test for the quantitative screening kits of T-2 toxin.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.351-357
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• 1994

The levels of maternal immunity enhancing factor(MIEF), which is an immunomodulatory protein identified from bovine colostrum, were determined by indirect competitive enzyme-linked immunosorbent assay(ELISA) for the colostrum and normal milk collected during the first two weeks of lactation. The mean concentration of MIEF in the colostrum of the first day of lactation was $109\;{\mu}g/ml$, and fell from the third day of lactation to $3{\sim}4\;{\mu}g/ml$. The molecular weight of the purified MIEF determined by reducing SDS-PAGE and TSK G2000SW column chromatography was 22,000 and 24,000 daltons, respectively, showing that MIEF is a monomeric peptide in its native form. To examine the capacity of MIEF to induce differentiation of B Lymphocytes, human tonsillar Iymphocytes were cultured in the presence of different concentrations of MIEF, and then antibody secreting cells were enumerated by enzyme-linked immunospot(ELISPOT) assay. When added to cultures of human tonsillar Lymphocytes, MIEF induced differentiation of resting B Iymphocyte to antibody secreting plasma cells as efficiently as LPS.

• Journal of Microbiology and Biotechnology
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• v.18 no.11
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• pp.1858-1861
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• 2008

A PCR-enzyme-linked immunosorbent assay (PCR-ELISA) was developed for the rapid and sensitive detection of L. monocytogenes. PCR primers generating a 132-bp amplicon and a capture probe able to hybridize to the PCR amplicon were designed based on the L. monocytogenes-specific hly gene encoding listeriolysin. The detection limit of PCR-ELISA for L. monocytogenes was determined to be as low as 10 cells per PCR reaction, and this level of detection was achieved within 5 h. These results indicate that the PCR-ELISA provides a valuable tool for the rapid and sensitive detection of L. monocytogenes for the ready-to-eat food industry.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.538-543
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• 2000

This study was conducted to develop an enzyme-linked immunosorbent assay(ELISA) for the determination of cooked goat meat. Muscle proteins were extracted from goat meat by heating at $98^{\circ}C$ for 15 min. Major thermostable(TS) protein, whose size and pI are 36 and 38 kDa and 4.5 respectively, were purified by DEAE-Sephadex A-50 and Sephadex G-75 column chromatography. The TS protein was immunized into rabbits in order to produce goat specific antibodies. Competitive indirect ELISA(ciELISA) was established by using the anti-TS antibody. The antibody showed high reactivity toward the TS antigen and the boiled goat meat extract but it did not show any reactivities toward extracts of boiled chicken, pork, lamb, and beef. Thus, this ciELISA developed in this study could be applicable to identify goat species from cooked meat.

• Journal of fish pathology
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• v.9 no.2
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• pp.169-176
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• 1996

An indirect double antibody enzyme-linked immunosorbent assay (ELISA) was developed for rapid detection of a new virus isolated from abnormally swimming salmonid fish, RVS (Retrovirus of salmonid). Results using brain tissue homogenates, and infected cell cultures are described. The sensitivity of the methods is $10^{2.6}$ $TCID_{50}/100{\mu}l$ of the examined cell culture fluid. The specificity was confirmed by the ELISA inhibition test and virological examinations. Viral antigen could be detected in artificially infected fish tissue homogenates. The assay will allow the diagnosis of RVS-infected fish within a day.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.16.1-16.8
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• 2013

Objectives Fish vitellogenin (VTG) is produced in the female liver during oogenesis through the estradiol cycle and produced in the male liver by endocrine disrupting chemicals (EDCs) such as alkylphenols. In this study, we propose that the VTG concentration in the pale chub could be detected using monoclonal antibodies and polyclonal antibodies against vitellin (Vn) in a VTG enzyme-linked immunosorbent assay (ELISA) system. Methods Monoclonal antibodies and polyclonal antibodies were produced using the Vn extracted from the matured ovum of the ovary. The VTG was extracted from the plasma of the male pale chub. The Vn and VTG were confirmed by measuring the molecular weight of their proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and the specificity of the antibodies was checked through western blotting methods. The assay system was validated with respect to optimal assay concentrations, specificity, recovery, and intra- and inter-assay variations. Results The Vn consisted of two protein bands with apparent molecular weights of 64 and 37 kDa. The SDS-PAGE indicated protein weights of 146 and 77 kDa in the VTG. The assay range was 15.6 ng/mL to 2,000 ng/mL, and the value of the intra- and inter-assay variations were within 10.0% and 14.7%, respectively. The recovery rate was $99.5{\pm}5.5%$. Conclusions A sandwich ELISA was developed that could be used to qualify the VTG of pale chub in screening for EDCs. Pale chub is an ideal species for observing estrogen activity in the environment because of its extensive habitat and extensive food chain. The ELISA developed here would be more favorable than those for other species for determining the effect of long-term food chain accumulation of EDCs in aquatic environments.