• Applied Chemistry for Engineering
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• v.1 no.2
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• pp.249-255
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• 1990

The conditions for separation and identification of anionic and nonionic surfactants by thin layer chromatography were investigated. Polyoxy alkylene-type nonionic surfactants were identified by the distribution of alkyl chain and alkylene oxide. Various polyoxyethylenated nonyl phenols were easily distinguished by densitometer. Some anionic surfactants were identified by $R_f$ and color, and the mixtures of anionic and nonionic surfactants were separated. Polyoxyethylenated fatty acid was separated into three parts of diester, monoester and polyethylene glycol, respectively, and the mixed ratio was determined by densitomer. All the experiments were carried out in 13-20 minutes, and the length of run was 80mm.

• Analytical Science and Technology
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• v.25 no.5
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• pp.284-291
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• 2012

Bloody fingerprint is a very important evidence. In this study, we confirmed the enhancement effects of ninhydrin, leucocrystal violet (LCV), fuchsin acid, iodine and dimethylaminocinnamaldehyde (DMAC) on bloody fingerprints which were deposited on paper. Bloody fingerprint were deposited on paper sequentially and used after drying at room temperature. If a ridge of bloody fingerprint was clear, ninhydrin and LCV was the most effective but was not good for invisible ridge. Fuchsin acid reagent dyed paper surface so that the contrast of enhanced bloody fingerprint was decreased. Although bloody fingerprint was enhanced with iodine reagent, but the developed color was very weak after reaction. We thought that the enhancement effect of iodine to bloody fingerprint was negligible. Also, the enhancement effect of DMAC reagent to relatively clear bloody fingerprint was not good. However, it was very effective to faint or invisible ridge. By washing with methanol, contrast of enhanced bloody fingerprint was increased.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.148-153
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• 2009

In this study, we have developed a fluorescence chromatographic assay for the quantification of total cholesterol in serum, which is a well-known risk predictor for cardiovascular diseases. The new assay system consists of a chromatographic strip in a cartridge, enzyme buffer containing cholesterol esterase, cholesterol oxidase, horseradish peroxidase, and color developer AEC, and a laser fluorescence scanner. The correlation coefficient (r) between cholesterol concentration and relative fluorescence units was 0.968 in the new assay, showing a reliable linearity through the tested range of cholesterol. Recovery test and comparability with a Hitachi 747 instrument showed 106.5-94% and r = 0.939 (p<0.001), respectively. The new assay system for cholesterol was developed as a pre-POCT platform conducted in clinics since it is fast (8 min) and uses a small volume of sample ($5\;{\mu}l$), and it may be applied for on-site diagnostics to replace expensive automated biochemical analyzer.

• Analytical Science and Technology
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• v.6 no.1
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• pp.121-129
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• 1993

UV/VIS spectrophotometer interfaced with HPIC(High Performance Ion Chromatography) has been applied to the determination of lanthanide elements. The separation of lanthanide elements with HPIC helped to avoid erroneous analytical results due to interferences. Individual lanthanide elements at ppm level were separated on a HPIC CS5 column using pyromellitic acid and oxalic acid. The individual lanthanide elements were detected at 520nm following post-column reaction with PAR. Sm, Eu, Gd, Y, Tb, Dy, Ho, Er, Tm, Tb, and Lu were separated by pyromellitic acid. La, Ce, Pr and Nd were separated by oxalic acid. Appropriate pH of pyromellitic acid for separation was at pH 2.99.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.470-474
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• 2003

DNA sequence information on small-subunit rRNA gene (16S rDNA) obtained from food-poisoning bacterial culture was used to investigate the presence of bacterial pathogens in food. By reverse dot blot detection method, presence of food-poisoning bacteria could be confirmed on hybridization of digoxigenin-labeled 16S rDNA Polymerase Chain Reaction (PCR) primer product and biotin-labeled specific oligonucleotide probe. Escherichia coli, Bacillus cereus. and Salmonella sp. were used as the representative food-poisoning bacterial microorganisms. An oligonucleotide probe, based on the variable region of 16S rRNA gene, was used as the specific probe. These tools may be more useful than classic biochemical method for rapid identification of contaminated food.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.522-525
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• 2011

In this study, an established enzyme-linked immunosorbent assay and immuno-chromatography technique are combined to fabricate an immuno-strip sensor for the detection of S. aureus. The immuno-strip is manufactured by using four different functional membranes. The capture antibody is immobilized on the nitrocellulose membrane due to the high affinity and the capillary action through porous membranes induces a flow of sample. A colorimetric signal is appeared according to the enzyme reaction and is analyzed by the digital camera (qualitative analysis) and home-made image analysis software (quantitative analysis). Under the optimal conditions, samples with S. aureus in the range of $2.7{\times}10^4{\sim}2.7{\times}10^7CFU/mL$ can be detected by the colorimetric method within 30 min.

• Applied Chemistry for Engineering
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• v.32 no.1
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• pp.10-14
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• 2021

mCherry is one of the well-understood red fluorescent proteins which has a similar tertiary structure as GFPs, but pH resistant due to the lack of hydrogen bond network. Whereas mCherry-I202T showed far-red fluorescence and also pH sensitive property because of the additional hydrogen bond formed by substituting Ile of 202 amino acid sequence on mCherry with Thr. In order to verify the pH sensitive characteristic of mCherry-I202T owing to the extension of hydrogen bond, UV-vis spectrum was measured over the range of acidic to basic pH. We also demonstrate further possibilities of applying mCherry-I202T as a pH sensor.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.183-196
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• 1991

In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1：50 and serum dilution of 1：100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r＝0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

• Tuberculosis and Respiratory Diseases
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• v.48 no.2
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• pp.191-202
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• 2000

Background: Bronchial asthma is characterized by airway hyperresponsiveness(BHR) and inflammation. The cyclooxygenase(COX) is believed to be one of the important enzymes in these inflammatory reactions. Recently, the COX was divided into two isoforms, COX1 and COX2. COX2 is induced by lipopolysaccharide and some cytokines at the inflammation site. Prostaglandin E2(PGE2), produced from COX2, may affect airway inflammation. The purpose of this study is to evaluate the effect of COX2 inhibitor on COX2 expression, plasma PGE2, airway resistance and histologic finding in an animal asthma model. Methods : Sprague-Dawley rats were divided into 3 groups. The normal control group did not receive any treatment, but the asthma control group was sensitized by ovalbumin but not treated with the COX2 inhibitor(nimesulide, Mesulid$^{(R)}$). The treatment group was sensitized and treated with nimesulide. Specific airway resistance(sRaw) before and after nimesulide ingestion was investigated. The PGE2 level in the plasma was examined and COX2 immunogold-silver stain on lung tissue was performed. Results: sRaw and eosionophilic infiltration on airway, which increased in the asthma control group, was compared to normal control(p=0.014). However, there was no difference in eosinophilic infiltration between asthma control and treatment groups(p=0.408) and no difference in COX2 expression on bronchiolar epithelium among the three groups. Plasma PGE2 levels were not statically different among the three groups. Conclusion: The role of COX2 in the allergen-induced BHR was not significant The effect of nimesulide was not observed on BHR, COX2 expression, and plasma PGE2 level. Therefore, COX2 may not be a major substance of allergic asthma.

• Research in Plant Disease
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• v.9 no.2
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• pp.94-98
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• 2003

To produce antibodies against Pseudomonas tolaasii and P. agarici, lyophilized P. tolaasii and P. agarici ($5{\times}10^7$ cfu/ml) and Freund, s adjuvant were immunized into rabbits 4 times. The specificity and sensitivity of the antibodies were evaluated by immunodiffusion test and indirect enzyme-linked immunosorbent assay (id ELISA). The ${\alpha}$-P. tolaasii antibody was very specific only against P. tolaasii, while ${\alpha}$-P. agarici antibody was not specific and showed a high cross reactivity toward P. tolaasii with detection limit concentration of $2{\times}10^3$ cfu/ml. However, the cross reactivities of ${\alpha}$-P. agarici antibody toward the related species including P. reactans were very low. Our results showed that ${\alpha}$-P. tolaasii and ${\alpha}$-P. agarici antibodies against P. tolaasii and P. agarici, respectively, might be useful for rapid and simple detection of the causal agents of bacterial brown and yellow blotches in cultivated oyster mushrooms.