• 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.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.301-304
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• 1990

In the mosquitocidal delta-endotoxins from Bacillus thuringiensis subsp, isruelensis and B. thuringiensis subsp. darmstudiensis 73E10-2, were contained an immunologically homologous protein. The homologous protein was confirmed from Ouchterlony test, irnmuno-electrophoresis, and enzyme linked immunoassay by polyclonal antibodies against the delta-endotoxins of both strains.

• KSBB Journal
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• v.30 no.1
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• pp.1-10
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• 2015

Nanomaterial-based artificial enzymes (Nanozymes) have attracted recent attention because of their unique advantageous characteristics such as excellent robustness and stability, low-cost production by facile scale-up, and longterm preservation capability that are critically required as an alternative to natural enzymes. These nanozymes exhibit natural enzyme-like activity, and they have been applied to diverse kinds of detection methods for disease-associated biomolecules such as DNAs, proteins, cells, and small molecules including glucose. To highlight the progress in the field of disease diagnostics using nanozyme, this review discusses many nanozyme-based detection methods categorized by the types of target biomolecules. Finally, we address the current challenges and perspectives for the widespread utilization of nanozyme-based disease diagnostics.

• Infection and chemotherapy
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• v.50 no.4
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• pp.346-349
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• 2018

In 2015, rapid human immunodeficiency virus (HIV) testing was implemented in all 25 public health centers in Seoul. During March and December 2015, 20,987 rapid HIV tests were performed, of which 116 (0.5%) were positive. Compared to those of the period before application of the rapid HIV test in place of conventional enzyme immunoassay method, the number of HIV tests performed and the number of positive results increased by sevenfold and twofold, respectively. In conclusion, expansion of the provision of rapid HIV tests in public health centers increased the number of voluntary HIV tests.

• IMMUNE NETWORK
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• v.8 no.3
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• pp.82-89
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• 2008

Background: Although a skin test is the primary option for detecting allergen-specific IgE in clinics, the serum IgE immunoassay is also important because it allows for the diagnosis of allergy without any accompanying adverse effect on the patient. However, the low detection limit of IgE levels by immunoassay may restrict the use of the method in some occasions, and improving its sensitivity would thus have a significant implication in allergy-immunology clinics. Methods: In this study, we attempted to detect specific serum IgE by using immuno-polymerase chain reaction (IPCR) which combines the antigen-antibody specificity of enzyme-linked immunosorbent assays (ELISAs) with the amplification power of PCR. Results: Our results demonstrated that Blo t5-specific serum IgE can be detected by IPCR with a 100-fold higher sensitivity than ELISA, and cross-reactivity of serum IgE to other mite allergens is able to be analyzed by using only $0.3{\mu}l$ of serum sample. Use of real-time IPCR seemed to permit more convenient determination of specific serum IgE as well. Conclusion: We believe that IPCR can serve as a valuable tool in determining specific serum IgE, especially when the amount of serum sample is limited.

• KSBB Journal
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• v.20 no.2 s.91
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• pp.123-128
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• 2005

We have addressed two important issues of immunosensing biochips, including the construction of antibody functionalized suface for efficient affinity reactions and the development of a signal registration strategy that converts biospecific reactions into highly quantifiable electrochemical and/or optical signals. The developed immunoassay reaction is an integrated version of enzyme-mediated immunoprecipitaion reaction, which is widely used in immunohistochemistry, and electrochemical signaling reaction. For the evaluation of analytical performance of fabricated immunosensing biochips, signaling for mouse IgG in antiserum was conducted. Applications of the developed strategy have been found for the evaluation of histology chemicals and for the signal amplification for array-type biochip analysis.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.147-154
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• 2005

Objective: In this study, the effects of Liriope Platyphylla against LPS-induced inflammation was investigated. Methods: Cell viability was determined using the MTT assay. To identify expressions of COX-2 and iNOS mRNA, RT-PCR was performed. Assessment of PGE2 synthesis was performed using the PGE2 immunoassay. Measurement of NO synthesis was performed using the NO detection. Result : The MTT assay revealed that Liriope Platyphylla exerted no significant cytotoxicity in the microglial BV2 cells. RT-PCR analysis revealed that the mRNA levels of COX-2 and iNOS were significantly decreased in the LPS- and 5 mg/ml Liriope Platyphylla treated group. From the PGE2 immunoassay and NO detection, PGE2 and NO synthesis was significantly suppressed in the LPS- and 5 mg/ml Liriope Platyphylla treated group. Conclusion : In these study, Liriope Platyphylla was shown to suppress PGE2 and NO production by inhibiting LPS-stimulated enhancement of COX-2 enzyme activity and iNOS expression. It is very possible that Liriope Platyphylla can offer a valuable mode of therapy for the treatment of brain inflammatory diseases.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1605-1608
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• 2003

To development an immunodetection method for DDT, 1,1,1-trichloro-2,2-bis(4-chorophenyl)ethane (p,p'-DDT) and its metabolites (p,p'-DDA, p,p'-DDE, p,p'-DDD), five derivatives of DDT haptens have been synthesised and characterized as coating ligands for antibody evaluation. The appropriate lengths of linkers were introduced to investigate a matching pair of coating ligand and antibody. Among these hapten derivatives, 2,2-bis(4-chlorophenyl)acetic acid (DDA), 5,5-bis(4-chlorophenyl)-5-hydroxypentanoic acid (DDHP) and 5,5-bis(4-chlorophenyl)-5-chloropentanoic acid (DDCP) were conjugated with keyhole limpet hemocyanin (KLH) for its use as an immunogen. The bovine serum albumin (BSA) conjugates of these derivatives were prepared as a coating ligand for monoclonal antibody screening. Fifteen monoclonal antibody clones were screened using these probes. 6,6-Bis(4-chlorophenyl)-6-hydroxyhexanoic acid (DDHH) and 3-[6,6-Bis(4-chlorophenyl)-6-hydroxyhexanoylamino]propanoic acid (DDHHAP), in addition to the above hapten derivatives, were conjugated to ovualbumin (OVA) and bovine serum albumin (BSA) for their use as coating ligands to measure the titration level of the antibody and the displacement of free analytes. The indirect competitive ELISA results indicate that the titration level and free analyte displacement were greatly influenced by the DDT derivatives and carrier proteins used. Three matching pairs of monoclonal antibodies and coating ligands were selected for the DDT immunoassay: antibody clone 1A3 and coating ligand DDA-OVA, 1A1 and DDHHAP-BSA, and 1A4 and DDHP-OVA.

• 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.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.112-123
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• 1994

${\gamma}$-Glutamyltransferase (GGT: E.C. 2.3.2.2.) is a glycoprotein enzyme which is involved in glutathione metabolism and amino acid transport through the plasma membrane. It is distributed widely in several organs including liver and kidney. Several isozymes of GGT have been reported and some of the isozymes may be associated with hepatocarcinogenesis. We have produced six monoclnal antibodies (mAbs) against GGT purified from the liver of 2-acetamidofluorene (AAF) treated rats. All of the six mAbs were obtained by immunizing mice with liver GGT Six hybridomas which produced anti-GGT Abs were extensively subcloned and injected into the peritoneal cavity of BALB/c mice to obtain large quantities of Abs. These mAbs were purified from ascites by ammonium sulfate precipitation and protein A sepharose CL-4B column chromatography. Using these mAbs we preformed enzyme-linked immunosorbent assay (ELISA), radioimmunoassay (RIA), immunohistochemistry (IHC), and autoradiography (ARG) to study the distribution of GGT isozyme in tissue. The results indicate that GGT-mAb 1 is specific for the AAF treated liver GGT, GGT-mAb 5 for the normal liver GGT, and GGT-mAb 6 for the normal kindey GGT. These mAbs may be used to evaluate the distribution of GGT isozymes in different tissues.