• Food Science and Biotechnology
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• v.15 no.6
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• pp.990-992
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• 2006

In a previous study, we obtained polyclonal antibodies against the organophosphorus insecticide fenitrothion and developed an enzyme-linked immunosorbent assay (ELISA) for this pesticide. Using these antibodies and an enzyme tracer, a direct competitive ELISA method specific for fenitrothion using a dipstick format was developed. Dipstick ELISA using antibodies to fenitrothion immobilized on an Immunodyne membrane allowed the quick visual detection of fenitrothion at concentrations above $10\;{\mu}g/L$. The $IC_{50}$ value of dipstick ELISA using reflectance detection was $27\;{\mu}g/L$ with a detection limit of $2\;{\mu}g/L$. The recovery of fenitrothion from spiked lettuce and rice samples using the dipstick ELISA ranged from 87-107%.

• 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.

• Korean Journal of Veterinary Service
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• v.21 no.2
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• pp.107-115
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• 1998

In order to establish a rapid, sensitive and specific diagnostic method for detection of antibody to Brucella abortus, a enzyme-linked immunosorbent assay(ELISA) was adapted. The diagnostic efficacy of the established ELISA was compared with that of the standard tube agglutination test for B abortus. 1. It was found that the optimal concentration of antigen for this ELISA was 5$\mu\textrm{g}$/ml, the optimal dilution of conjugate was 1 : 2000, and the optimal dilution of serum was 1 : 200, respectively. 2. Cut off value in this ELISA was 1,102 that was determined by mean absorbance(at 492nm) of tube agglutination test negative serum added with the triple value of the standared devation. 3. The relationship between the tube agglutination test and ELISA was showen high corresponding rate with sensitivity(96.3%) and specificity(98.1%). 4. The efficacy of the ELISA for detection of B abortus antibody was compared with tube agglutination test In brucellosis outbreak farm. The sensivity of ELSIA was higher than tube agglutination test.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.36-41
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• 2010

The Hen's egg is widely used in many processed foods as an ingredient and is one of the most prevalent food allergens in children. To detect egg proteins in processed foods, we developed a competitive indirect enzyme-linked immunosorbent assay (ciELISA) using an anti-ovomucoid (OM) antibody, which was produced by immunization of rabbits with OM, the most heat-stable component of the egg proteins. The detection limit of this quantitative assay system was 30 ng/mL. Cross-reactivity of the anti-OM antibody toward OM, ovalbumin, skim milk, casein, whey protein isolate, and isolated soy protein was 100, 0.4, 0.2, 0.04, 0, and 0%, respectively. In the spike test of egg white powder in milk replacer, commercial sausage, and in-house sausage, the assay recoveries ($mean{\pm}SD$) were $129{\pm}13.7%$, $73.9{\pm}12.5%$, and $65.5{\pm}13.6%$, respectively. When egg white in a commercial crab meat analog and sausage was determined by ciELISA, the assay recovery was found to be 108% and 127%, respectively. The combined results of this study indicate that this novel ciELISA for OM detection could be applied for the quantification of hen's egg proteins in processed foods.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.387-392
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• 2011

Enzymes are being used in various fields due to their unique property of substrate specificity. Enzyme-linked immunosorbent assay(ELISA) has enabled the detection of various antigens by reporting the binding event of antigen and antibody via enzyme-catalyzed reaction. However, the sensitivity improvement of conventional ELISA has been limited because only one enzyme molecule is conjugated to one molecule of antibody. To overcome this limitation and further improve the sensitivity of ELISA, there have been efforts to increase the number ratio of enzymes to antibody. Recently, the nanobiocatalytic approaches, with their successful enzyme stabilization, improved the performance stability as well as sensitivity in a modified protocol of ELISA. The present paper introduces the basic principle of ELISA, and the recent efforts to improve sensitivity and performance stability of ELISA by using the nanobiocatalytic approaches.

• 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.

• Food Science of Animal Resources
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• v.43 no.6
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• pp.989-1001
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• 2023

Processed foods containing pork fat tissue to improve flavor and gain economic benefit may cause severe issues for Muslims, Jews, and vegetarians. This study aimed to develop an indirect enzyme-linked immunosorbent assay (iELISA) based on a monoclonal antibody specific to thermal stable-soluble protein in pork fat tissue and apply it to detect pork fat tissue in heat-processed (autoclave, steam, roast, and fry) beef meatballs. To develop a sensitive iELISA, the optimal sample pre-cooking time, coating conditions, primary and secondary dilution time, and various buffer systems were tested. The change in the iELISA sensitivity with different 96-well microtiter microplates was confirmed. The detection limit of iELISA performed with an appropriate microplate was 0.015% (w/w) pork fat in raw and heat-treated beef. No cross-reactions to other meats or fats were shown. These results mean that the iELISA can be used as an analytical method to detect trace amounts of pork fat mixed in beef.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.509-514
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• 2020

Satsuma dwarf virus (SDV) seriously damages citrus production by reducing the quality and yield of fruit. To avoid contamination with SDV, mother trees are checked to be SDV-free in advance of nursery tree distribution. In this study, we compared an immunochromatographic assay (ICA) kit with double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for large-scale diagnosis of SDV in orchardgrown trees in Shizuoka Prefecture, Japan. The two methods gave conflicting results for 11 of 1,705 samples, all of which were negative by DAS-ELISA but positive by ICA. The samples scored as positive by either DAS-ELISA or ICA were analyzed by reverse transcription polymerase chain reaction and all were confirmed to be positive. These results validate the use of ICA as a screening method for large-scale diagnosis. Strain discrimination revealed that 16 of 22 isolates belonged to SDV, while citrus mosaic virus (CiMV) infection only and co-infection (SDV and CiMV) were in a minority.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.612-619
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• 2004

A competitive direct enzyme-linked immunosorbent assay (cdELISA) was developed for selective and rapid detection of a glycopeptide antibiotic, teicoplanin (TP). TP was conjugated to bovine serum albumin (BSA) for use as an immunogen. Repeated subcutaneous injections of 0.5 mg of the conjugate was effective in generating specific polyclonal antibody (PAb) toward TP in rabbits, as determined by cdELISA. TP-horseradish peroxidase conjugate (TP-HRP) was used as an enzyme marker. The cdELISA was developed based on a competition reaction between TP-BSA PAb and TP-HRP conjugate. The TP-BSA PAb was highly sensitive (detection limit, 0.3 ng/ml and specific toward teicoplanin, showing no cross-reactivity to other glycopeptide antibiotics including vancomycin. There were good correlations ($r^2$=0.84 and 0.76, respectively) between cdELISA and microbiological assay, and high-performance liquid chromatography. The cdELISA system developed in this work is expected to be useful not only for selective and rapid monitoring of TP but also for study of TP pharmacokinetics.

• YAKHAK HOEJI
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• v.45 no.6
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• pp.656-663
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• 2001

The quality of an intravenous immunoglobulin preparation (IVIG) is reflected by the degree of nonspecific activation of complements, the so-called anticomplementary activity (ACA). ACA of aggregates in IVIG was investigated using method by the European Pharmacopoeia and Clq-coated microtiter enzyme-linked immunosorbent assay (ELISA). Both the EP method and the ELISA method showed a dose response curve with the amount of complements bound increasing with the percentage content of aggregates in immunoglobulin standard. The correlation between the two tests was good (r=0.96, r=0.99). However, the correlation was not found when the ACA (EP method) of IVIG product was compared with its aggregate percentage. These results emphasize that the method of aggregate formation affects ACA and that estimation of the percentage distribution of aggregates by HPLC may not reflect ACA. In analysing WIG product for Clq binding activity test with the ELISA, the result by using Protein A-HRP correlated with aggregate percentage (r=0.84). But the correlation decreased (r=0.48) when the result used Protein A-AP(having poorer sensitivity than HRP) was compared with aggregate percentage. As a result, some variation between the two methods, due to differences in assay principles, is to be expected. However, ELISA technique has the advantage in that it is easier to perform, more precise and less subject to reagent variability, and is the more suitable screening method than HPLC analysis.