• Analytical Science and Technology
• /
• v.25 no.5
• /
• pp.284-291
• /
• 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
• /
• v.24 no.2
• /
• pp.148-153
• /
• 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.

• Applied Chemistry for Engineering
• /
• v.10 no.2
• /
• pp.196-200
• /
• 1999

The electrochemical properties of 9-methyl-2,3,6,7-tetramethoxyfluorene have been investigated by cyclic voltammetry in acetonitrile, dichloromethane, trifluoroacetic acid (TFA) and trifluoroacetic acid anhydride (TFAn). The first charge transfer for the compound in $CH_3CN$ appeared to be a quasi-reversible one-electron step. The second oxidation step from cation to dication was irreversible. However, the oxdition of the compound in a mixture of solvents containing $CH_2Cl_2$, TFA and TFAn was reversible for both the first and second charge transfer reactions. Since the electrolytic products display a darkblue color and can be stabilized in the solvent mixture, they may be used as an electrochromic material.

• Applied Chemistry for Engineering
• /
• v.23 no.1
• /
• pp.65-70
• /
• 2012

Structural changing materials which can induce the physical deformation of materials are interesting research topics with various potential applications. Particularly, light among many driving mechanisms is a non-contact energy source, hence the light-responsive system can be used where non-destructive, local irradiation, and remote control is needed. Here, a mainchain azobenzene polymer is synthesized and its physical and optical properties are observed and compared to that of a polymer having a light-responsive azobenzene moiety on its side chain. Further dispersion onto polyvinylalcohol hydrogel is made and its dual stability and actuation are observed upon UV-visible light irradiation. Extended azobenzene polymer blend films show an anisotropic light-actuation with non-polarized UV light at room temperature. This physical shape change is quite reversible and occurs at lower temperature than that of any other reported systems including liquid crystalline elastomers. It is successfully demonstrated that the simple physical azobenzene/polymer blending has a very good actuation compared to that of LCEs which need an elaborate chemical design and it can be further used in the areas requiring a dimensional shape change.

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

• Journal of Food Hygiene and Safety
• /
• v.6 no.3
• /
• pp.111-117
• /
• 1991

We examined to develop the enzyme linked immunosorbent assay (ELISA) for determination of zearalenone in animal feeds. Zearalenone was first converted to 6'-(carboxymethyl) zearalenone oxime(zearalenone oxime) to get a coupling site and then conjugated to bovine serum albumin(BSA) for use as immunogen and to horseradish peroxidase(HRP) for use as enzyme marker. Antibody against zearalenone was obtained after 11 weeks of immunization of rabbit with zearalenone oxime-BSA. Cross reactivity of the antibody with ${\alpha}-zearalanol,\;{\beta}-zearalenol,\;{\alpha}-zearalanol\;and\;{\beta}-zearalanol$ were 168, 46, 26 and 20% respectiviely. A simple procedure was devised for the screening of zearalenone in feeds using ELISA. Feeds samples(5g) were extracted by blending with 25 ml of methanol-phospate butTered saline-dimethylformate(70 : 29 : 1) and the extract was filtered and aqueous filterate analyzed. It took only 1 hours to do whole procedure for the analysis of zearalenone in feeds by the direct competitive ELISA, and detectable limit was 1-100 ppb. Using this procedure, only 4 of 24 feed samples showed positive results with 3.93-7.43 ppb levels.

• Korean Journal of Food Science and Technology
• /
• v.35 no.3
• /
• pp.470-474
• /
• 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 Biological Chemistry
• /
• v.19 no.4
• /
• pp.233-242
• /
• 1976

In this paper, new methods for the determination of the total and the individual saponin glucosides were proposed. One of them was a colorimetric method following Two-dimensional Thin layer chromatography. And the method employing Thinchrograph TFG-10 or Densitorol DMU-33C followed the separation of the saponins by means of a preparative thin layer chromatography. In accordance with the density of the chromatogram of each saponin, Thinchrogram or Densitogram of the individual saponin fraction was plotted and determined.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.15 no.1
• /
• pp.69-74
• /
• 1986

In order to examine the effect of 'Lactobacillus plantarum' inoculation on the maturation of cured loin ham, bacteriological and biochemical changes in meat were investigated during curing periods. The results were summarized as follow; On the bacteriological changes of cured ham, during curing periods, the number of coliform group were decreased. while psychrotrophic and halo-tolerant bacteria were increased until the 4 days. In the brine solution after the 7days of the curing, the number of coliform group were decreased the 7 days, but psychrotophic and halo-tolerant bacteria were increased until the 7 days of curing. The pH value of the meat and curing solution were sharply decreased at the one day, since these were slightly increased from 4 days. The color development of cured meat was showed 84.05 % development of within the 7 days of curing. Glutamic acid contents among the 17 kinds of amino acid were the highest at the 7 and 10 days of curing. The 13 kinds of fatty acids detected from at the all sample and total contents of unsaturated fatty acid were slightly decreased during curing.

• Journal of the Korean Chemical Society
• /
• v.21 no.6
• /
• pp.445-448
• /
• 1977

This study was carried out to understand the activity of ${\alpha}$-chymotrypsin, a proteolytic enzyme, to a oligopeptide in the presence of various coloring food additives. 1. The melting point of synthetic oligopeptide, Asp-Arg-Val-Tyr-Ile-His-Pro-D-Ala, ((8-D-Ala) angiotensin Ⅱ) was 210∼$212^{\circ}C$. Chemical formula and molecular weight were $C_{44}H_{67}N_{13}O_{12}{\cdot}2CH_3COOH{\cdot}H_2O$ and 970.08, respectively. 2.The amino acid rations by acid hydrolysis were Asp : 1.01, Arg : 1.03, Val : 1.00, Tyr :40.94, Ile : 1.00, His : 1.05, Pro : 1.04, D-Ala : 1.03. 3. ${\alpha}$-Chymotrypsin cleaved the oligopeptide bond between tyrosine and isoleucine (Tyr-Ile). 4. The addition of food coloring additives as determined by paper chromatogram, did not influence the inhibitory activity of ${\alpha}$-chymotrypsin on oligopeptide, (8-D-Ala) angiotensin II.