• Biomedical Science Letters
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• v.5 no.1
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• pp.11-15
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• 1999

Thyroxine (3,5,3',5'-L-tetraiodothyronine; T$_4$) is the most commonly measured thyroid hermono for the diagnosis of various thyroid disorders. Although radioimmunoassay (RIA) is still considered as the reference technique for the measurement of T$_4$, it is generally regarded that RIA has its primary disadventages in handling the wastes and controling the human and material resources. Therefore, establishment of enzyme-linked immunosorbent assay (ELISA) has of great significance. To verify the usefulness of our enzyme immunoassay, we have obtained the standard dose response curve of T$_4$ in patient's sera which is inversely proportional to the amount of herseradish peroxidase (HRP) conjugated monoclonal antibody of T$_4$ bound to the wells. The correlation coefficient (r) between the ELISA and chemiluminescent assay was 0.444 (n=38). Thus we have investigated the establishment of rapid and sensitive competitive ELISA assay method for detection of T$_4$ in patient's sera.

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.213-217
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• 1995

A screening method has been developed for detecting sulfamethazine(SMZ) contamination of meat or feeds by using horseradish peroxidase (HRP) labeled protein A (Prot AHRP)and an indirect competitve enzyme-linked immunosorbent assay(ELISA). The assay is based on competitve binding of guinea pig anti-SMZ with SMZ in smaple and SMZ-gelatin conjugate(SMZ.GEL). Percent binding (B.Bo$\times$100) was calculated from the absorbance in the absence (B0) and presence (B) of SMZ. By the sandard curve prepared by plotting log(SMZ) vs percent binding of each known reference solution, the detection limit was 1.0ppb or less. Cross reacton with sulfadimethoxine, sulfaguaniding, sulfamerazine, sulfamthoxpyridazine, sulfanilamide, sulfisomidine and sufisoxazole were not observed. But sulfamerazine crossreacted in the test. The EC-50 value (concentration causing 50% inhibition of color development compared with blank) of sulfamerazine was 2.0 ppm. Further quality control will make the ELISA system ideal for the detection of SMZ in meat or feeds.

• 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.

• Journal of Food Hygiene and Safety
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• v.13 no.2
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• pp.129-134
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• 1998

To develop an enzyme-linked immunosorbent assay (ELISA) for nivalenol (NIV), we produced polyclonal antibodies against tetraacetyl nivalenol (Ac4-NIV) and established ELISA conditions. Ac4-NIV-hemisuccinate conjugated to bovine serum albumin (Ac4-NIV-HS-BSA) was immunized with Freund's adjuvants into rabbits subcutaneously several times. By use of the antiserum showing the highest titer and Ac4-NIV-HS-HRP conjugate, we established competitive direct ELISA (cdELISA). Standard curve of cdELISA showed that the detection range of Ac4-NIV was about 10~5,000 ng/ml (ppb). The cross-reactivities of the polyclonal antibody towards Ac4-NIV and acetyl T-2 were 100 and 70% respectively, and those towards NIV, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, triacetyl deoxynivalenol, fusarenonX, and T-2 were less than 0.1%. When cdELISA was applied to NIV-spiked corns followed by extraction with 70% acetonitrile and acetylation with acetic anhydride in pyridine, the recovery rates of the Ac4-NIV were 108, 143, and 70% (average, 107%) in the levels of 100, 300, and 1,000 ng/g (ppb), respectively.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.18-24
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• 1987

Mouse monocolonal antibodies to Hepatitis B surface antien (HBsAg) were prepared and their functional capabilities tested by the method of solid phase enzyme linked immuno sorbent assay (ELISA). HBsAg binding studies inicated that one monoclonal antibody 6E-1-1 bound more HBsAg at a faster rate than the other monoclonal antibodies. Also, for the binding inhibition studies with the selected monoclonal antibody 6E-1-1, one monoclonal antibody 8D-3-6 didn't exhibit binding inhibition for HBsAg. Then, a simultaneous ELISA method was developed for the immunodiagnosis of HBsAg. Different combinations of two monoclonal antibodies as solid phase and horseradish peroxidase (HRPO) labeled phase were studied. The combination of monoclonal antibody of higher affinity constant (6E-1-1) immobilized in a solid phase and monoclonal antibody of lower affinity constant (8D-3-6) as a HRPO laeled phase was more sensitive when two monoclonal antibodies of different affinity constants for HBsAg were prepared.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.228-233
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• 1998

Seed storage proteins have been used for studying biochemical genetics and end-use quality aspects. We conducted enzyme-linked immunosorbent assay (ELISA) and one-dimensional SDS-PAGE (1D SDS-PAGE) to evaluate different cereal crop species and Korean wheat lines for rye secalin proteins. The antisecalin antibody showed consistent specificity for rye secalin with little cross-reactivity to gliadins. Immunological cross-reactivities measured by the ELISA technique using competition assay showed significant differences of absorbance among rye, triticale, wheat-rye translocated wheat and non-translocated wheat. The absorbance values were lowest in rye followed by triticale, translocated wheat and non-translocated wheat. The ELISA for discrimination of wheat-rye translocation on the basis of antigen-antibody reactivity showed that none of the Korean wheat lines possessed 1RS and secalin proteins. The competitive ELISA experiment demonstrated specific determination for secalin that was originated from rye chromosomal parts. The result of 1D SDS-PAGE for identifying rye secalin subunits showed all three rye specific secalin protein subunits (75 KDa, 45 KDa, and 40 KDa) for rye and triticale, and 1RS specific secalins (45 KDa and 40 KDa) for 1AL/1RS and 1BL/1RS translocated wheats. All Korean wheats were lacking 1RS of rye chromosome and secalin.

• Bulletin of the Korean Chemical Society
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• v.24 no.3
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• pp.334-338
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• 2003

A simple synthetic method for haptens of organophosphorus (OP) pesticides with a spacer arm (aminocarboxylic acid) attached at the pesticide thiophosphate group was developed and was applied to the synthesis of haptens for the OP fungicide tolclofos-methyl. Using the haptens, a selective enzyme-linked immunosorbent assay (ELISA) for tolclofos-methyl was developed. One of the haptens was coupled to BSA to use as an immunogen. Rabbits were immunized with this conjugate to obtain polyclonal antibodies to tolclofos-methyl. The antisera were screened against another hapten coupled to ovalbumin (OVA). Using the serum with highest specificity, an antigen-coated ELISA was developed, which showed an $IC_{50}$ of 160 ng/mL with the detection limit of 20 ng/mL. The antibodies showed negligible cross-reactivity with other OP pesticides. An antibody-coated ELISA was also developed, which showed an $IC_{50}$ of 410 ng/mL with a detection limit of 130 ng/mL.

• Korean Journal of Veterinary Research
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• v.30 no.2
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• pp.187-192
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• 1990

The Presence and quantity of protein A in Staphylococcus hyicus subsp hyicus isolates from pigs were determined by indirect hemagglutination test and enzyme-linked immunosorbent assay(ELISA). Cell-bound and extracellular protein A was demonstrated in 87.7% and 36.0% of 489 isolates, respectively, by indirect hemagglutination test. When contents of the protein A were estimated by ELISA method, all of the isolates that were positive to protein A in indirect hemagglutination test produced extracellular protein A of less than 1ng/ml. Most of the isolates produced cell-bound protein A of less than 1ng/ml, whereas 28 isolates produced 1 to 35ng/ml and 11 isolates produced 25 to 108ng/ml.

• Research in Plant Disease
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• v.25 no.3
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• pp.131-135
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• 2019

Cylindrocarpon destructans causes ginseng root rot and produces radicicol that has an antifungal effect. In this study, we developed a method to detect this fungus using enzyme-linked immunosorbent assay (ELISA). Secreted proteins of C. destructans were used as antigens to obtain C. destructans-specific IgG from mouse. Out of 318 monoclonal antibodies generated from mouse, two antibodies (Cd7-2-2 and Cd7-2-10) showed highest specificity and sensitivity. Indirect ELISA using both antigens successfully detected C. destructans in soils, but direct ELISA using IgG conjugated with horseradish peroxidase failed to detect antigens in soils. The indirect ELISA developed here can efficiently detect the fungus and help manage ginseng root rot disease in fields.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.269-276
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• 2018

Rabies virus (RABV)-specific antibodies in animals and humans are measured using standard methods such as fluorescent antibody virus neutralization (FAVN) tests and rapid fluorescent focus inhibition tests, which are based on cell culture systems. An alternative assay that is safe and easy to perform is required for rapid sero-surveillance following mass vaccination of animals. Two purified monoclonal antibodies (4G36 and B2H17) against RABV were selected as capture and detection antibodies, respectively. A genetically modified RABV, the ERAGS strain, was propagated and concentrated by polyethylene glycol precipitation. Optimal conditions for the RABV antigen, antibodies, and serum dilution for a blocking enzymelinked immune sorbent assay (B-ELISA) were established. We evaluated the sensitivity, specificity, and accuracy of the B-ELISA using serum samples from 138 dogs, 71 raccoon dogs, and 25 cats. The B-ELISA showed a diagnostic sensitivity of 95.8-96.3%, specificity of 91.3-100%, and accuracy of 96.0-97.2% compared to the FAVN test. These results suggest that the B-ELISA is useful for sero-surveillance of RABV in dogs, raccoon dogs, and cats.