• YAKHAK HOEJI
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• v.40 no.2
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• pp.135-140
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• 1996

Ion-selective poly(vinyl chloride)(PVC) membrane electrodes for the determination of the calcium antagonist verapamil and its pharmaceutical preparations were described. Verapam il-superchrome garnet Y(SGY), lumogallion(LG), acid red 97(AR97), Dragendorff(DD) and Meyer reagent ion pairs were inverstigated as an electroactive compound for membrane electrode. Stable potentiometric response was obtained with azo dye at pH 6.5-4.0 and with DD, and Meyer reagent at pH 6.5-3.0. The best plasticizer was 49w/w% 2-nitrophenyl octyl ether for azo dye, and 65.3w/w% tri(n-butyl) citrate for DD and Meyer reagent. Potentiometric response slopes of optimized membrane electrodes based on SGY, LG, AR97, DD, and Meyer complex for verapamil were 52.49, 54.88, 50.81, 54.13 and 49.31 mV/dec., respectively. Lower limits of linear range were $1.0{\times}10^6M$ for SGY, LG, and AR97, while those for DD and Meyer reagent were $4{\times}10^{-6}M$. Detection limits for all these electrodes were $1{\times}10^{-5}M,\;4{\times}10^{-6}M,\;1.8{\times}10^{-6}M,\;8{\times}10^{-7}M,\;and\;1{\times}10^{-6}M$ with relative standard deviation of 2.56, 3.6, 3.96, 2.56, 3.20%, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.788-795
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• 2015

Two dimensional-fluorescence difference gel electrophoresis (2D DIGE) is an emerging technique for comparative proteomics, which improves the reproducibility and reliability of differential protein expression analysis between samples. The purpose of this study was to investigate bovine pregnancy-specific proteins in the proteome between bovine pregnant and non-pregnant serum using DIGE technique. Serums of 2 pregnant Holstein dairy cattle at day 21 after artificial insemination and those of 2 non-pregnant were used in this study. The pre-electrophoretic labeling of pregnant and non-pregnant serum proteins were mixed with Cy3 and Cy5 fluorescent dyes, respectively, and an internal standard was labeled with Cy2. Labeled proteins with Cy2, Cy3, and Cy5 were separated together in a single gel, and then were detected by fluorescence image analyzer. The 2D DIGE method using fluorescence CyDye DIGE flour had higher sensitivity than conventional 2D gel electrophoresis, and showed reproducible results. Approximately 1,500 protein spots were detected by 2D DIGE. Several proteins showed a more than 1.5-fold up and down regulation between non-pregnant and pregnant serum proteins. The differentially expressed proteins were identified by MALDI-TOF mass spectrometer. A total 16 protein spots were detected to regulate differentially in the pregnant serum, among which 7 spots were up-regulated proteins such as conglutinin precursor, modified bovine fibrinogen and IgG1, and 6 spots were down-regulated proteins such as hemoglobin, complement component 3, bovine fibrinogen and IgG2a three spots were not identified. The identified proteins demonstrate that early pregnant bovine serum may have several pregnancy-specific proteins, and these could be a valuable information for the development of pregnancy-diagnostic markers in early pregnancy bovine serum.

• Restorative Dentistry and Endodontics
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• v.21 no.2
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• pp.517-529
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• 1996

The purpose of this study was to evaluate the apical sealing ability of the Thermafil endodontic obturation technique and to compare it with lateral condensation technique. 42 straight canals from extracted human anterior teeth and 42 curved canals(> $25^{\circ}$) from maxillary and mandibular molar teeth were selected. And 80 of them were divided into four groups, 20 canals respectively. The teeth in prior two groups had straight canals and the other two groups had curved canals. The rest of four canals served as positive and negative controls. After resecting anatomical crowns, all canals were prepared using a standard step-back technique. Lateral condensation was used to obturate two groups, one group of straight ones the other curved. And Thermafil obturators were also used in the same two groups. Obturated teeth were infiltrated by India ink for a week, decalcified and cleared with 5% nitric acid and methyl salicylate. The apical leakage and the frequency of filled lateral and accessory canals were measured with stereomicroscope and also apical extrusion of sealer and gutta-percha and obturation time were checked and the data were analyzed statistically(one-way ANOVA, t-test, Chi-square test). The results were as follows : 1. There was no significant difference in the degree of dye penetration between Thermafil and lateral condensation groups(p>0.05). 2. Apical extrusion of sealer and gutta-percha occurred significantly more often with Thermafil obturators in straight canals(p<0.05), but not significantly different in curved canals(p>0.05). 3. Canal obturation time with Thermafil obturators was significantly faster than lateral condensation (p<0.05). 4. The Thermafil groups showed a higher frequency of filled lateral and accessory canals than in the lateral condensation groups. But the difference was not statistically significant (p>0.05).

• Textile Coloration and Finishing
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• v.3 no.2
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• pp.34-42
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• 1991

The effects of electrolyte on dyeing properties of cotton fiber with Congo Red have been studied at 90, 70 and $40^{\circ}C$. Each dyeing carried into an infinite bath with $1\times10^{-4}$ mol/l of Congo Red and with various concentration of electrolytes. The results obtained from this study were as follow; 1. The equilibrium adsorption of dye $(C_\infty)$ values decreased with increasing dyeing temperature, $C_\infty$ values increased in the order KCl>NaCl>LiCl. 2. The values of apparent diffusion coefficients $(D_a)$ increased with increasing dyeing temperature, but $D_a$ values decreased in the order KCl$D_a$ values decreased with increasing electrolyte concentration. 4. Effect of electrolytes decreased with increasing dyeing temperature. 5. The values of standard affinities of dyeing $(-\triangle\mu^{\circ})$, the standard heats of dyeing $(-\triangleH^{\circ})$, and the standard entropies $(-\triangleS^{\circ})$, increased in the order KCl>NaCl>LiCl. 6. Equilibrium adsorption isotherm curve were Freundlich type, and in the Equation y=a.x$^{n}$ , the values of a and n increased in the order KCl>NaCl>LiCl. 7. The value of $-\triangle\mu^{\circ}$, $-\triangleH^{\circ}$, and $-\triangleS^{\circ}$, decreased with increasing electrolyte concentration.

• Journal of Food Hygiene and Safety
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• v.35 no.2
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• pp.109-117
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• 2020

This study aimed to develop an analytical method for determination of 18 dyes in livestock and fishery products by liquid chromatograph-tandem mass spectrometry (LC-MS/MS). The developed method was validated for linearity, accuracy, limit of quantifications (LOQ) and recovery based on the CODEX guideline (CAC/GL-71). Target matrices (beef, pork, chicken, egg, milk, flatfish, eel, and shrimp) were extracted using acetonitrile (containing 1% of acetic acid) and then, purified with C₁₈ and primary secondary amine (PSA). Calibration linearity was obtained (r²>0.98) and LOQs were 0.002 mg/kg in animal products. The recoveries of dyes were ranged from 63 to 112% and relative standard deviations (RSDs, %) were less than 15%. The residues of 18 dyes were investigated in real samples (n=124) collected from retail markets in South Korea. As a result, a total of seven samples showed positive results for target analytes in fish samples. However, there was no violation according to the maximum residue limits set by the Korean Food Code. The proposed method will be used for routine analysis of dye residues in livestock and fishery products.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6081-6086
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• 2014

Background: To evaluate the effectiveness of Microlux/DL with and without toluidine blue in screening of potentially malignant and malignant oral lesions. Materials and Methods: In this diagnostic clinical trial clinical examination was carried out by two teams: 1) two oral medicine consultants, and 2) two general dentists. Participants were randomly and blindly allocated for each examining team. A total of 599 tobacco users were assessed through conventional oral examination (COE); the examination was then repeated using Microlux/DL device and toluidine blue. Biopsy of suspicious lesions was performed. Also clinicians opinions regarding the two tools were obtained. Results: The sensitivity and, specificity and positive predictive value (PVP) of Microlux/DL for visualization of suspicious premalignant lesions considering COE as a gold standard (i.e screening device) were 94.3%, 99.6% and 96.2% respectively, while they were 100%, 32.4% and 17.9% when considering biopsy as a gold standard. Moreover, Microlux/DL enhanced detection of the lesion and uncovered new lesions compared to COE, whereas it did not alter the provisional clinical diagnosis, or alter the biopsy site. On the other hand, adding toluidine blue dye did not improve the effectiveness of the Microlux/DL system. Conclusions: The Microlux/DL seems to be a promising adjunctive screening device.

• YAKHAK HOEJI
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• v.56 no.4
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• pp.222-229
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• 2012

In order to determine acetylcholine and choline in the biological samples, the specific enzymes of acetylcholinesterase (AChE) and choline oxidase (ChO), which utilize acetylcholine and choline as substrates, were employed to convert substrates to $H_2O_2$. The produced $H_2O_2$ was coupled to 4-aminoantipyrine/phenol with peroxidase (PO) yielding quinoneimine dye which was measured at 508 nm. In the present enzymatic spectrophotometric analysis the product at the equilibrium state was measured considering accuracy, precision, time and cost of the analysis. The developed analytical method yielded good linearity (calibration curve; $A_{508}$=9534[acetylcholine]+0.009, correlation coefficient ($R^2$); 0.999) with detection limit of $1.11{\times}10^{-7}M$, reasonable precision (relative standard deviation; 0.10~1.62% at $2.5{\times}10^{-6}M{\sim}1.25{\times}10^{-4}M$) and accuracy (relative error; -0.24~0.97% at $4.13{\times}10^{-6}M{\sim}1.01{\times}10^{-4}M$) for acetylcholine chloride standard solution. The concentrations of acetylcholine and choline in human serum were found as $3.20{\times}10^{-5}M$ and $1.14{\times}10^{-4}M$, respectively. The brain tissues of Sprague-Dawley strain rat contained 9.82${\mu}g/g$ of acetylcholine and 6.53 ${\mu}g/g$ of choline in the cerebrum, while 7.37 ${\mu}g/g$ of acetylcholine and 5.34 ${\mu}g/g$ of choline in the cerebellum.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.17 no.1
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• pp.64-80
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• 1991

The SKINTEX Method is based on a two-compartment physico-chemical model which includes a Biomembrane Barrier in compartment one and an organized macromolecular matrix in compartment two. Test samples absorb onto or permeate through the keratin/collagen Biomembrane Barrier and then can interact with the organized macromolecular matrix. Changes in the integrity of the barrier release a dye indicator: Changes in the matrix can alter its transparency. The sum of these two responses is read spectrophotometrically at 470nm. An early investigation of 950 chemicals and formulations in the SKINTEX System produced results which were 89% concordance to in vivo Draize dermal irritation results obtained with 24-hour occluded application of test samples with-out abrasion and standard scoring. Alkaline materials were analyzed in a specialized SKINTEX AMA Protocol. In this early study, the model did not distinguish nonirritant test materials and formulation with PDII(Primary Dermal Irritation Index)in the range from 0 to 1.2, A High Sensitivity Assay Protocol(HSA)was developed to amplify the changes in both compartments of this model and provide more accurate calibration of these changes. A study of 60 low irritation test samples including cosmetics, household products, chemicals and petro-chemicals distinguished nonirritants with PDII $\leq$ 0.7 for 26 of 30 nonirritants. A second protocol was developed to evaluate the SKINTEX model predictability with respect to human irritation. The Human Response Assay (HRA )has been optimized based on differences in penetration and irritation responses in humans and rabbits. An additional 32 test materials with different mechanisms and degrees of dermal toxicity were evaluated by the HRA. These in vitro results were 86% concordant to human patch test results. In order to further evaluate this model, a Standard Chemical Labelling (SCL) Protocol was developed to optimize this system to predict Draize dermal irritation results after a 4-hour application of the test material. In a study of 52 chemicals including acids, bases, solvents, salts, surfactants and preservatives, the SCL results demonstrated 85% concordance to Draize results for a 4-hour application of test samples on non-abraded rabbit skin. The SKINTEX System, including three specialized protocols, provided results which demonstrated good correlation to the endpoint of dermal irritation in man and rabbits at different application times.

• Carbon letters
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• v.11 no.3
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• pp.206-210
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• 2010

Removal of dyes Reactive Blue 221, N Blue RGB and Acid Blue MTR using two different samples of activated carbon by static batch method was studied. Experimental data on optical density of solutions at different concentrations ranging from 10 to 100 mg/L and of solutions after adsorption on activated carbon samples were measured. Calibration curves were plotted and the amount of dye $q_e$ adsorbed was calculated. The data was fitted to Langmuir and Freundlich isotherms for two different carbon samples and different concentration and pH values. Constants were calculated from the slope and intercept values of the isotherms. Coefficient of correlation $R_2$ and Standard Deviation SD were also noted. The data fitted well to the isotherms. Carbon sample $C_1$ showed higher potential to adsorb all the three dyes. Adsorption was higher at lower concentrations. Carbon sample $C_2$ showed better adsorption in acidic pH as compared to in alkaline pH. From the analysis of the data capacity of $C_1$ and $C_2$ to remove the dyes from water have been compared.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1258_1259
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• 2009

염료감응형 태양전지 (dye-sensitized solar cell; DSC)는 경제성 한계에 달한 Si 태양전지를 대체할 수 있는 유력한 후보로서, 지금까지 많은 연구개발로 큰 효율향상을 기록했다. 다양한 연구 분야 중에서도, 투명전도성 막과 전해질 층간의 접촉으로 발생하는 전자의 재결합을 막기 위해 삽입하는 compact layer는 ZnO dip-coating, $TiCl_4$ dip-coating, Ti sputtering 등 다양한 제조방법이 제시되었다. 본 연구에서는 $TiCl_4$ 용액을 이용해 spin-coating 방법으로 $TiO_2$ compact layer를 제조하는 시도를 했다. 기존 dip-coating 방법과의 비교를 통해서 본 연구의 spin-coating 방법에 의한 효과를 확인한 결과, standard DSC 대비 33.4%, dip-coating 방법으로 compact layer를 삽입한 DSC 대비 6%의 효율 향상을 기록했다.