• Korean Journal of Clinical Laboratory Science
• /
• v.42 no.1
• /
• pp.32-37
• /
• 2010

The author was performed to investigation of current status of prevalence for anti-hepatitis C virus (HCV) among the health-checkup adults in Jeonbuk province. A toal of 1,553 (male 1,046, female 507) serum samples were diagnosed by 3rd generation enzyme immunoassay (EIA) for anti-HCV. Total prevalence of anti-HCV was 0.9%, and prevalence of male and female were 0.8% and 1.2%, respectively. The prevalence of female was higher than male. According to ages group, prevalence of anti-HCV was highest in 60 age group, but it was not found in 20 age group. 14 samples with anti-HCV positive were diagnosed by EIA for hepatitis B virus surface antigen (HBs Ag), by chemiluminescence immunoassay (CLIA) for serum albumin, alanine transaminase (ALT) and asparagine transaminase (AST). Positive for HBs Ag was not found. The mean of serum albumin levels was 4.5 g/dL, and mean of ALT and AST were 34.3 IU and 31.9 IU, respectively. Through this study, I know that the prevalence of anti-HCV among adults in Jeonbuk, and suggest that the positive of anti-HCV persons who have lower serum albumin, normal to mild elevations in serum enzymes are chronic hepatitis.

• YAKHAK HOEJI
• /
• v.31 no.2
• /
• pp.64-69
• /
• 1987

Monoclonal antibodies against human chorionic gonadotropin (hCG) were prepared and characterized by examining isotype, epitope binding, cross reactivity and affinity constants. And a sandwich type enzyme immunoassay for native hCG was developed with solid phase monoclonal antibody against the conformational determinant expressed only on native hCG and horseradish peroxidase conjugated monoclonal antibody against the $\beta$-subunit of hCG. The assay was sensitive to 1 mIU hCG/ml and shown a linear response up to 200 mIU hCG/ml. The cross reactivity for luteinizing hormone and $\beta$-subunit of hCG were 1% and 0.18%, respectively.

• Archives of Pharmacal Research
• /
• v.21 no.3
• /
• pp.231-235
• /
• 1998

A sensitive enzyme immunoassay for serum TSH has been developed utilizing the tight binding between biotin and avidin, and three layered protein polystyrene beads as solid phase. To increase binding capacity of TSH and sensitivity of the assay, the polystyrene beads were coated sequentially with mouse immunoglobulin as first layer, rabbit antimouse immunoglobulin as second layer and monoclonal anti-TSH as third layer. A serum sample was incubated simultaneously with a monoclonal anti-TSH immobilized polystyrene beads and a second monoclonal anti-TSH covalently attached to biotin. After washing, the antibody bound serum TSH-anti-TSH-biotin complex is reacted with horseradish peroxidase (HRP)-labeled avidin. Following second wash, the bound HRP activity was measured calorimetrically. Reproducible results were obtained within 4 hours for serum TSH in the range between $0{\mu}\textrm{IU}$ml and ${50}{\mu}\textrm{IU}$ml with detection limit of $0.1{\mu}\textrm{IU}$ per test.

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

• Journal of Pharmaceutical Investigation
• /
• v.39 no.4
• /
• pp.309-314
• /
• 2009

An enzyme immunoassay (EIA) was validated for quantitation of cacitriol in human plasma. Calcitriol was immunoextracted with immunocapsules, which contain monoclonal antibodies to calcitriol linked to solid phase particles in suspension with a vitamin D binding protein inhibitor. Calcitrol was eluated and the eluates were evaporated under a gentle stream of nitrogen gas. The absorbance of analytes was determined using a microplate reader (reference wavelength 650 nm; measurement wavelength 450 nm). The method was specific and sensitive enough to detect as low as 6.5 pmol/L of calcitriol. Linear calibration range was 6.5-491 pmol/L with correlation coefficient greater than 0.99. The overall accuracy was in the range of 83.8 to 111.2% and precision C.V. (%) 0.99 to 8.47%. The recovery was approximately 100% and stability was confirmed during storage and sample preparation. The pharmacokinetic parameters were calculated by baseline subtraction because calcitriol is an endogenous material. Following oral dose of calcitriol, the mean AUC$_{24h}$ was 1038${\pm}$539 pmol/Lhr and C$_{max}$ of 128${\pm}$63.1 pmol/L was reached at 3.50${\pm}$1.07 hr. The mean t$_{1/2}$ of calcitriol was 5.13${\pm}$2.10 hr. The present EIA method was successfully applied to study bioavailability after oral administration of 2 ${\mu}$g of calcitriol in healthy Korean subjects.

• Journal of Sensor Science and Technology
• /
• v.20 no.6
• /
• pp.400-405
• /
• 2011

This study introduced the development of a strip type disposable enzyme-linked immunosensor platform for the detection of IgG. Strips of the strip sensor were fabricated by using commercial nitrocellulose filter membranes and a housing holder for the strips was manufactured by using a standard injection molding process for a plastic material. An IgG-urease conjugate was prepared and used for the competitive immune-binding with sample IgG. From the enzymatic reaction between the conjugated urease and urea added, ammonia was generated and caused a localized alkaline pH change on the immobilized antibody band which was coated onto the sensor strips. This pH increase subsequently caused a color change of the antibody band in the presence of a pH indicator, phenol red. Used in conjunction with a competitive immunoassay format, the intensity of the color produced is directly linked with the concentration of target analyte, IgG, and specific measurement of IgG in a lateral flow immunoassay format was achieved over the range 100 ppb to 2000 ppb IgG.

• Clinical and Experimental Pediatrics
• /
• v.50 no.2
• /
• pp.143-150
• /
• 2007

Purpose : This study was conducted to validate enzyme immunoassay (EIA) for the quantitative measurement of human IgG antibodies specific for Haemophilus influenzae type b (Hib) capsular polysaccharide. Method : We evaluated specificity, repeatability, intermediate precision, accuracy, lower limit of quantification (LLOQ), and stability to validate standardized EIA for the quantitative measurement of human anti-polyribosylribitol phosphate (PRP) IgG antibodies. Results : The results indicated that this EIA showed specificity to HbO-HA antigen and repeatability and intermediate precision were within acceptance criteria (repeatability: $CV{\leq}15%$, intermediate precision: $CV{\leq}20%$). The EIA-derived results from this laboratory were equivalent to those obtained by the standard radioactive antigen binding assay (RABA) for quantitation of anti-PRP antibodies in the 28 sera. Spiking recovery result was within acceptance criteria ($100{\pm}20%$). The precision and accuracy of samples in LLOQ were from -14.7 to -4.7% in nominal values, which were within acceptance criteria (precision: $CV{\leq}25%$, accuracy: ${\pm}25%$). Freeze-thaw stability and short term temperature stability were within ${\pm}20%$ of acceptance criteria. Conclusions : The EIA which is performed at the Center for Vaccine Evaluation and Study Ewha Medical Research Institute, is an appropriate serologic assay which can be used for quantitation of anti-PRP IgG antibodies in human sera.

• The Journal of the Korean Society for Microbiology
• /
• v.22 no.4
• /
• pp.473-483
• /
• 1987

Present study was undertaken to find when is right time for vaccination against Measles, Mumps and Rubella and what is the seropositive conversion rate after those vacinations. For this purpose, sera from 106 infants and children adimitted in Prediatric Department of Won Kwang University Hospital, Iri, Chonbuk, Korea were divided into 3 groups, such as (1) Vaccination group with definite information when it was given, (2) Unknown group whether vaccination was given or not, (3) Not vaccinated group. They were tested of IgG and IgM antibodies against Measles, Mumps and Rubella using Enzyme Immunoassay method and the following results were obtained. 1. Infants below 6 month of age showed to have IgG antibodies which seemed to have been transferred from mother in 87.8%(29/33) for Measles, 78.8%(26/33) for Mumps and 39.4%(13/13) for Rubella. And they showed IgM antibodies which are thought to have been produced by recent infection in 24.2%(8/33) for Measles, 48.5%(16/33) for Mumps and 9.1%(3/33) for Rubella. 2. Positivity of antibody IgG against Rubella was observed remarkably lower than it is against Measles and Mumps being only 39.4%(13/33) in $0{\sim}5$ month, 30.8%(8/26) in $6{\sim}11$ months, 30%(3/10) in $12{\sim}14$ months and 62.9%(22/35) in $18{\sim}36$ months of age. 3. ${\Delta}OD's$ of IgG and IgM antibodies against Measles were observed increasing with age being 0.444, 0.220 in $0{\sim}5$ months, 0.326, 0.134 in $6{\sim}11$ months, 0.581, 0.140 in $12{\sim}14$ months, 0.512, 0.000 in $15{\sim}17$ months and 0.887, 0.278 in $18{\sim}36$ months of age, respectively. 4. ${\Delta}OD's$ of IgG and IgM antibodies against Mumps were observed increasing with age being 0.427, 0.340 in $0{\sim}5$ months, 0.400, 0.249 in $6{\sim}11$ months, 0.694, 0.314 in $12{\sim}14$ months, 0.539, 0.165 in $15{\sim}17$ months and 0.854, 0.350 in $18{\sim}36$ months of age, respectively. 5. Vaccination for Measles, Mumps and Rubella is generally to start at 15 months of age in Korea, by which age their antibodies are found to exsist in more than 80% of tested samples. So, it seems to be very reasonable to start the vaccination schedule at earlier age than it does currently. 6. From the present study, it seems to have been clearly confirmed that Enzyme Immunoassay method is a reliable method with good reproducibility for mass survey of IgG and IgM antibodies against Measles, Mumps and Rubella in infants and children.

• Bulletin of the Korean Chemical Society
• /
• v.18 no.5
• /
• pp.515-519
• /
• 1997

In a competitive enzyme immunoassay, the performance was tested with different analyte-enzyme conjugates (signal generators) in their binding constants to antibody. Analyte (progesterone)-enzyme (glucose oxidase; GO) conjugates were chemically synthesized and purified by using a gel column with an immobilized antibody to progesterone. In an elution range from the column, four peaks were detected by measuring total enzyme activities. Results from further analysis indicated that the first peak contained mainly unreacted GO while the next three peaks conjugated GO with progesterone. These three conjugate preparations were compared in dose-response curves along with the unpurified mixture. The purified conjugates showed higher detection capabilities than did the mixture. Especially, the preparation in the second peak next to the free GO peak improved the detection limit five times. This performance was comparable to that of a progesterone-horseradish peroxidase conjugate that has been identified to have one progesterone ligand.

• Proceedings of the Zoological Society Korea Conference
• /
• 1998.10b
• /
• pp.361.2-361
• /
• 1998

No Abstract, See Full Text