• Journal of Korean Medical Science
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• v.33 no.46
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• pp.304.1-304.7
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• 2018

Background: The Republic of Korea has a very low prevalence of human immunodeficiency virus (HIV) infection, but the number of new HIV diagnoses has steadily risen, strongly indicating a large number of undetected HIV infections. Thus, it is important for Korean public health authorities to adopt and encourage cost-effective HIV detection tools, such as rapid HIV screening tests. In this study, we aimed to evaluate the cost-effectiveness of enzyme-linked immunosorbent assays (ELISA) and rapid tests in a public health center (PHC) setting. Methods: We developed a decision analytic model to assess the per-examinee cost and the cost-effectiveness of identifying HIV patients in a PHC setting using two HIV testing strategies: conventional HIV screening by ELISA versus rapid HIV testing. Analysis was performed in two scenarios: HIV testing in an average-risk population and in a high-risk population. Results: Compared to the ELISA, the rapid test was cost-saving and cost-effective. The per-examinee cost was USD 1.61 with rapid testing versus USD 3.38 with ELISA in an average-risk population, and USD 4.77 with rapid testing versus USD 7.62 with ELISA in a high-risk population. The cost of identifying a previously undiagnosed HIV case was USD 26,974 with rapid testing versus USD 42,237 with ELISA in an average-risk population, and USD 153 with rapid testing versus USD 183 with ELISA in a high-risk population. Conclusion: Rapid testing would be more cost-effective than using conventional ELISA testing for identifying previously undiagnosed HIV-infected cases in Korea, a country with extremely low HIV prevalence.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.79-84
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• 1990

A single inoculation of combined vaccines of Newcastle disease and avian infectious bronchitis of chicken, in a form of gel-oil emulsion type (gel-OEV) was tested their immunogenecity in chickens. The results were summerized as follows: 1. Average minimum and maximum ELISA antibody titers of ND were recorded 2407 and 13144 respectively. In the case of IB, 1824 and 4496 were recorded as minimum and maximum titers. 2. The distribution of average proportional groups, in the lowest and the highest, were 1.6 and 7.0 in ND ELISA and 1.4 and 2.8 in IB ELISA antibody titers. 3. ND ELISA antibody titers were significantly increased upto 7th week after the vaccination. On the other hand, IB ELISA antibody titers were raised upto 4th week after the vaccination.

• Journal of Food Hygiene and Safety
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• v.10 no.1
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• pp.1-6
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• 1995

In order to establish the enzyme linked immunosorbent assay(ELISA) of sterigmatocystin produced by Aspergillus versicolor, we experimented and obtained following results. Two of three rabbits which had been immunized with sterigmatocystin-hemiacetal-BSA produced antibodies against sterigmatocystin at 15 weeks. The produced antibodies were specific for sterigmatocystin and sterigmatocystin-hemiacetal but didn't cross react with other sterigmatocystin analogues in a significant degree. DMF : 4% KC1 (18 : 2) mixed solution was most effective to dissolve sterigmatocystin. For the preparation of sample solution to determine sterigmatocystin by ELISA, sample was extracted with CHC13 and dried, than the dried sample was redissolved with 100 ${mu}ell$ DMF + 4% KC1 mixture. 10~1,000 ng/$m\ell$ level of standard sterigmatocystin could be applied to the established ELISA. When artifically contaminated rice were assayed by the ELISA, the average recovery of sterigmatocystin spiked to 25~500 ng/g was 109% (97~116%), and mean interwell coefficient of variation was 21% (11~28%).

• Journal of Environmental Health Sciences
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• v.20 no.3
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• pp.54-60
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• 1994

We established ELISA method which is more rapid and safe than conventional analytical method, and then analyzed concentration of ochratoxin A in the rices by ELISA method. The results were as follows: 1. Since ochratoxin A molecular does not contain the group for coupling reaction, it was first proposed to have the function of an antigen. As a result of conjugation of ochratoxin A-BSA derivatives, one molecular of BSA was conjugated with 13 moleculars of ochratoxin A. 2. On the basis of established ELISA to apply for immuno analytical method of ochratoxin A, the minimal level of detection by ELISA method was at 0.5 ppb. 3. Rices (42) were collected from homes of Kyoungnam districts through November 1992 to December 1992, as a result of analysis, two of these were positive. Rice samples of R-1 and R-9 represented ochratoxin A levels of 6.0 ng/g and 10 ng/g, respectively.

• Journal of Environmental Health Sciences
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• v.22 no.1
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• pp.51-56
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• 1996

In order to detect the T-2 toxin accumulation in the animal tissues, T-2 toxin, produced by Fusarium sporotrichioides M-1-1, was injected to mouse by 0, 1 and 2 mg per kilogram of body weight, respectively, and T-2 toxin extracted from serum and organs were analyzed by the indirected competitive ELISA. The indirect competitive ELISA established in the laboratory can be check less than 0.1 ppb level of T-2 toxin and average recovery of T-2 toxin spiked was 80~113% in animal samples such as serum, liver and kidney. After 6 weeks of treatment with 2 mg of T-2 toxin per kg body weight, T-2 toxin was accumulated in serum (133.0 ng/ml), liver(1.4 ng/g) and kidney(14.3 ng/g) of mouse injected with 2 mg of toxin per kg body weight.

• Parasites, Hosts and Diseases
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• v.56 no.1
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• pp.71-74
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• 2018

Soluble antigens from an axenic culture of Entamoeba histolytica were used to develop a commercial ELISA kit to quantify anti-E. histolytica antibodies in sera of patients with extraintestinal amebiasis in non-endemic settings. The diagnostic specificity and sensitivity of the test were assessed retrospectively using 131 human serum samples with amoebic serologic status available. They were selected according to their results in immunofluorescence (IFAT) and were separated in 2 sample categories: 64 sera with positive results by IFAT and 67 with negative results by IFAT. The sensitivity and specificity of the ELISA kit were assessed at 95.0% and 94.0% compared to the IFAT. The test can be useful to exclude a potential diagnosis of amebiasis and could be used as a screening method since ELISA is an automated technique.

• 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%.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.287-290
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• 1996

To control the maximum residue level (MRL) for sulfamethazine (SMZ) residues in pork tissue, a microbial inhibition method is a regulatory screening assay method in Korea. Microwell plate-based competitive enzyme immunoassay (ELISA) kit is avalable for routine screening of SMZ residues in pork tissue. One ELISA kit is evaluated. Phosphate buffer extracts of samples fortified with SMZ at 0, 1, 5, and 10 ng/g were used in a recovery test of the kit. Market pork samples were assayed by the kit. Recovery of sulfamethazine was 104% at 10 ng/g. Intraassay variations and interassay variations for the kit were 7.70% and 5.76%, respectively. Concentration causing 50% inhibition of color development compared with blanks was 16.4ng. The violative pork samples with over MRL (0.1 $\mu\textrm{g}$/g) was 4 of 32 cases (12.5%) by used ELISA kit. This result indicates a possibility of the ELISA kit for screening test of SMZ residues in pork tissue, and still needs a comfirmatory assay for mandatory purposes.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.481-487
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• 2002

A selective enzyme-linked immunosorbent assay (ELISA) for the insecticide chlorpyrifos was developed. Four haptens for chlorpyrifos were synthesized and two of them were used as immunogens after coupling to keyhole limpet hemocyanin by two differe nt approaches. Rabbits were immunized with either of them and the sera were screened against 4 haptens coupled to ovalbumin (OVA). Using the sera of highest specificity, an antigencoated ELISA was developed, which shows an I50 of 160 ppb with a detection limit of 10 ppb. An antibody-coated ELISA was also developed, which shows an $I_{50}$ of 20 ppb with a detection limit of 0.1 ppb. The antibodies showed negligible cross-reactivity with other organophosphorus pesticides except for insecticides chlorpyrifos-methyl and bromophos-ethyl, which makes these assays suitable for the selective detection of chlorpyrifos.

• 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.