• Analytical Science and Technology
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• v.13 no.1
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• pp.72-80
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• 2000

The HS/GC/MS method was performed to analyze the volatile organic compounds in waste sludge samples. This study was performed to establish the fundamental data by studying the effects of salt, equilibrium temperature and time in the volatile organic compounds analysis. The presence of salts have been found to increase the sensitivity. The peak area is increased from 1.07 to 2.61 times by adding the salts to the water sample, compared with a salt tree sample. The recoveries of target compounds have found between 90% and 127% at sample temperature of $85^{\circ}C$ for 30 min. This HS/GC/MS method can be applied to analyze the volatile organic compounds and organohalo compounds in the environmental matrix.

• Journal of Sensor Science and Technology
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• v.10 no.2
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• pp.125-133
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• 2001

Conducting polymer sensors show high sensitivity when exposed to volatile organic compounds gases at room temperature. The 8 sensor array using by polypyrrole and polyaniline has been fabricated by chemical polymerization for measuring sensing characteristics of VOCs gases. Conducting polymer was polymerized by using distilled pyrrole, aniline as a monomer and ammonium persulfate (APS) as an oxidant and dodecylbenzene sulfonic acid (DBSA) as a dopant. Dedoped film was synthesized by reverse voltage and redoped film was synthesized by using 1-octanesulfonic acid sodium salt as another dopant in electrochemical cell. The sensitivity and reversibility were influenced by doping, dedoping, redoping and thickness for the polypyrrole and polyaniline. We investigated the relation between the structure of conducting polymer and sensitivity of these sensors through the analysis of scanning electron microscope (SEM), scanning probe microscope (SPM) and $\alpha$-step.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.2
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• pp.71-79
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• 1988

For the purpose of producing low salt fermented anchovy by accelerated method with a strong proteolytic bacteria, in this study, a strong proteolytic bacterium was isolated from low salt fermented anchovy and its bacteriological characteristics and properties of protease were experimented. The results obtained were as fellows : three proteolytic bacteria, Aeromonas anaerogenes Barillus subtilis and Staphylococcus saprophyticus were isolated from low salt fermented anchovy($4\%\;of\;salt,\;4\%\;of\;KCl,\;0.5\%\;of\;lactic\;acid,\;6\%$of sorbitol and $4\%$ of alcohol extract of red pepper) after 40 days fermentation. Among these strains, which grow best at $30^{\circ}C$, pH 7.0, B. subtilis was found the best proteolytic strain and benefit for industrial use as shown $0.95\;hr^{-1}$ of specific growth rate, $89{\mu}g-Tyr/hr.ml$ of maximum activity after 12 hrs culture in TPY broth. The protease produced by by B. subtilis showed maximum activity at $35^{\circ}C$, pH 7.0, and molecular weight was estimated to be 23,000 by Sephadex G-100 filtration, and it was supposed to be a kind of metal chelator sensitive neutral protease from the results of strong sensitivity against EDTA, o-phenanthroline and metal ions such as $Cu^{2+},\;Ni^{2+},\;Fe^{2+}.Km$ value of that by method of Lineweaver-Burk was determinded to be $0.73\%$ for casein as a substrate.

• Journal of Pharmaceutical Investigation
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• v.40 no.6
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• pp.363-366
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• 2010

Identification of compounds that function as P-glycoprotein (P-gp) substrates or inhibitors can facilitate the selection and optimization of new drug candidates. The purpose of this study is to optimize the experimental conditions for in vitro P-gp assay using LLC-GA5 cells, which is a well-known transformant cell line derived by transfecting LLC-PK1 with human MDR1. The amount of rhodamine123 transported by the LLC-GA5 and LLC-PK1 cells was evaluated under the following experimental conditions: 3 different types of transport media, colchicine pretreatment or nontreatment of the cells in the culture media, and with and without poly-L-lysine coating of the culture plates. The assay sensitivity was found to considerably differ depending on the diluents used in the transport media. P-gp-mediated transport in LLC-GA5 cells was most clearly characterized in the Hanks' balanced salt solution based transport media. The sensitivity of P-gp-mediated transport was not changed by colchicine pretreatment or poly-L-lysine coating of the culture plates.

• Journal of Microbiology and Biotechnology
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• v.33 no.5
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• pp.698-705
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• 2023

Rapid diagnosis of methicillin-resistant Staphylococcus aureus (MRSA) is essential for guiding clinical treatment and preventing the spread of MRSA infections. Herein, we present a simple and rapid MRSA screening test based on the aggregation effect of mannose-binding lectin (MBL)-conjugated gold nanoparticles (AuNP), called the MRSA probe. Recombinant MBL protein is a member of the lectin family and part of the innate immune system. It can recognize wall teichoic acid (WTA) on the membrane of MRSA more specifically than that of methicillin-sensitive Staphylococcus aureus (MSSA) under optimized salt conditions. Thus, the MRSA probe can selectively bind to MRSA, and the aggregation of the probes on the surface of the target bacteria can be detected and analyzed by the naked eye within 5 min. To demonstrate the suitability of the method for real-world application, we tested 40 clinical S. aureus isolates (including 20 MRSA specimens) and recorded a sensitivity of 100%. In conclusion, the MRSA probe-based screening test with its excellent sensitivity has the potential for successful application in the microbiology laboratory.

• Korean Journal of Veterinary Research
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• v.30 no.3
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• pp.297-307
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• 1990

To establish an agar-gel immunodiffusion (AGID) test for detection of antibodies to Aujeszky's disease virus(ADV) in swine, the precipitating antigens were prepared by four procedures using the Aujeszky's disease virus, NYJ-1-87 strain isolated from the affected piglets in Korea. The optimal condition for AGID test and the properties of the antigens were investigated. To determine the optimal concentration of antigens, four antigens were experimentally prepared by concentrating the viral fluids by 1/30 to 1/200. It was proved that the antigen precipitated with ammonium sulfate at concentration of 1/100 was the most efficient to detect ADV antibodies by AGID test. When the relationship between the concentration of the antigens and the size of precipitating in radial immunodiffusion test was investigated, a high correlation coefficiency at r=0.95 (y=0.23x+23.4) was estimated, In study on the effects of various buffered salt solutions and agars on the sensitivity of AGID test by using the experimental ADV antigens, it was found that 0.05M tris buffer without sodium chloride at pH 7.2 induced the most distinctive precipitating lines, and that there was no significant differences in the sensitivity between the agarose and Noble's special agar. When the efficiency of AGID test was compared with serum neutralization(SN) test, the sensitivity of AGID test was 100% in SN titer over 1 : 16, 91.7% in SN titer of 1 : 8 and 57.1% in SN titer of 1 : 4. The specificity of AGID test compared with the sera with SN titer under 1 : 2 was 98.4%. Protein analysis of the antigens by SDS-PAGE indicated that antigen I and antigen III showed a specific band of polypeptides with molecular weight of 116 K in comparison with the control antigen. Antigen IV, treated with tween-80 and ammonium sulfate, revealed specific polypeptides bands at the molecular weights 45K, 98K and 150 K.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.185-191
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• 2003

The mechanism imparting salt tolerance to crop plants remains still unsolved, although soybean has been classified as a susceptible plant to NaCl. To determine optimum parameters on physiological responses for improving sensitivity of salinity in breeding program, soybean (Glycine max Merr., cv. "Gwan-gan") plants were grown in a greenhouse, treated 20 days after emergence for 7 days with NaCl at 0, 30, 60, and 90mM, corresponding to electric conductivity of 1.2, 4.4, 7.3, and 10.4 dS/m, respectively, and assessed 30 days after treatment. Chlorophyll contents were significantly decreased by NaCl ($0.4{\sim}1.0\;mg/g$) compared to control (1.2 mg/g). Photosynthesis rate by NaCl treatment at $0{\sim}90\;mM$ at flowering stage was ranged from 5.0 (control) to $9.6\;{\mu}mol/m^2/s$. Oxygen for respiration was consumed from 5.4 to $9.7\;{\mu}mol/m^2/s$ so that the ratio of $O_2$ (evolution:consumption) was increased with the increase of NaCl, indicating that $O_2$ consumption seems to go beyond $O_2$ evolution. Water potential of leaf at vegetative stage II was ranged from -0.6 to -1.8 MPa and the highest level was observed at mid-day. Water potential by salt stress was decreased with range of $-2.1{\sim}-2.7MPa$ compared to control. Transpiration was decreased from 17% to 20% by NaCl stress. Water vapor diffusing resistance of intercellular air space was affected significantly, increasing up to $16{\sim}24%$ compared to control by NaCl treatment. Salt-treated soybean tended to accumulate $Na^+$, specially in root, with reduced absorption of N, P, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ contents. Free proline content of soybean leaf as affected by different NaCl concentrations was increased 4.2 times ($184{\sim}434\;{\mu}g/g$) more than control. NaCl also increased activities of nitrate reductase and peroxidase by $28{\sim}161%$ and $3{\sim}22%$, respectively. The results show that physiological characteristics of soybean plants during assay were useful as the best parameters of salt stress or salt tolerance test to improve sensitivity in screening and breeding program among cultivars or germplasms.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.651-657
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• 2016

It is important to know know deleterious impact of deicing salt on plants for guidelines of planting along roads. The aim of this study was to determine the effect of calcium chloride ($CaCl_2$) on the growth and physiological characteristics of Liriope platyphylla and Pachysandra terminalis. The plants were grown from November of 2015 to March of 2016 in pots containing growing media with $CaCl_2$ at 0% (Control), 0.5%, 1.0%, 3.0%, and 5.0% (based on the weight). While plant growth and photosynthetic activity were significantly decreased in both plant species grown on the media with $CaCl_2$, the degree of sensitivity to $CaCl_2$ differed. The plant growth of Liriope platyphylla was considerably injured under higher than 3.0% of $CaCl_2$, whereas Pachysandra terminalis was all dead under higher than 1.0% of $CaCl_2$. This results indicate that Liriope platyphylla has higher degree of tolerance to the deicing salt than Pachysandra terminalis.

• Journal of Korean Port Research
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• v.14 no.3
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• pp.373-378
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• 2000

Oil spill in sea water is the most frequent and significant problem of marine pollution. As an early detection sensor of the pollution, an activated carbon coated quartz crystal is prepared and examined for its performance of detection sensitivity and stability. Powdered activated carbon and phenol resin is coated on the surface of the sensor and the sensor is baked for an hour. Adsorption of acetone dissolved in water and salt water is measured using frequency shift of quartz crystal at different concentrations of solute material. The outcome indicates that the sensor preparation is adequate and the measurement of solute concentration is stable and sensitive enough to be implemented on the monitoring of solute concentration is stable and sensitive enough to be implemented in the monitoring of organic pollution of sea water.

• Journal of the Korean Applied Science and Technology
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• v.17 no.3
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• pp.188-191
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• 2000

A new class of deep UV Photoresist based on the principles of chemical amplification was developed. This photoresist consists of three basic elements: a copolymer, blocked tetrabromobisphenol-A as a dissolution inhibitor and a photosensitive onium salt as a photoacid generator. On irradiation followed by a post exposure bake, tert-butoxycarbonyloxy phenyl group is converted to phenol group. Thus the initially base insoluble resin is converted under UV irradiation to a base soluble resin which may be preferentially removed by dissolution. This new photoresist display high sensitivity, 10 $mJ/cm^{2}$.