• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 2000.10a
• /
• pp.124-127
• /
• 2000

• Journal of IKEEE
• /
• v.28 no.1
• /
• pp.38-45
• /
• 2024

Most previous works about magnetic effect on plasma emission were interested in emission enhancement which was useful to various fields of plasma application. On the contrary, the following work is interested in plasma dissipation rarely reported in prior researches and expected to help advance plasma-controlling technique. Nd:YAG laser (1064 nm, 6 ns) was focused on three kinds of metals (Al, Ti and STS) and air. The permanent magnetic field (0.4 T) of Nd₂Fe₁₄B magnet was provided passing throughout laser-induced plasma. The spectra of plasma in both the presence and absence of the magnetic field were observed with varying laser power and delay time of the spectrograph. In this work it was uniquely discovered that the plasma always dissipated easily in the presence of magnetic field irrespective of the laser power. With the O I(777.42 nm)-line shape function fitted to Lorentz profile, its half width at half maximum (HWHM) was evaluated to verify that the magnetic field increased the plasma density. It is concluded that magnetic field facilitates not only plasma emission enhancement but also plasma dissipation, increasing recombination rate which is proportional to plasma density.

• Journal of the Korean Vacuum Society
• /
• v.17 no.6
• /
• pp.549-554
• /
• 2008

Nickel Chloride coated protein chip plates were developed by using a spin coating method after $H_2$ plasma treatment. The adsorption ability of histidine tagged protein was investigated at various times of plasma treatment. The properties of the nickel chloride and protein on the surface of the slides were assayed using particle size analysis and the extent of the protein adsorption was determined by using a bio imaging analyzer system. The results show that the ability of protein adsorption decreased as increasing the time of $H_2$ plasma treatment. The mechanism on the ability of protein adsorption at the plate surface is discussed on results and discussions. The results also suggest that the surface stabilization of protein chip plates treated by plasma technology may be applicable in biosensor markets.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2015.08a
• /
• pp.153-153
• /
• 2015

Application of the plasma is already highlighted as a new technology in the last few years. In these days, there are lots of attempt in various application with plasma in that it is known as an effective treatment to animal, plants, material and so on. Plasma in liquid, one of new plasma applications, has advantages in ability to treat bio-cell or solutions. For example, electro-surgery, water purification, radical generation and so on. Especially, plasma discharge in solutions is very useful technique and difficult to generate due to electrolysis, vaporization and something else. In this study, we have performed plasma discharge and checked sustainability of plasma in solution(saline 0.9%). And we have measured basic characteristics of plasma in liquid. Such as electrical energy and plasma density are calculated from discharging current and voltage. Also, its thermal energy is measured with IR camera.

• Korean Journal of Materials Research
• /
• v.25 no.11
• /
• pp.616-621
• /
• 2015

Atmospheric pressure plasma is used in the biological and medical fields. Miniaturization and safety are important in the application of apply atmospheric plasma to bio devices. In this study, we made a small, pocket-sized inverter for the discharge of atmospheric plasma. We used pulse power to control the neutral gas temperature at which the, when plasma was discharged. We used direct current of 5 V of bias(voltage). The output voltage is about 1 to 2 kilo volts the frequency is about 80 kilo hertz. We analyzsed the characteristics of the atmospheric plasma using OES(Optical emission spectroscopy) and the Current-Voltage characteristic of pulse power. By calculating of the current voltage characteristics, we were able to determine that, when the duty ratio increased, the power that actually effects the plasma discharge also increased. To apply atmospheric plasma to human organisms, the temperature is the most important factor, we were able to control the temperature by modulating the pulse power duty ratio. This means we can use atmospheric plasma on the human body or in other areas of the medical field.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.378.2-378.2
• /
• 2016

Biosensors currently suffer from severe non-specific adsorption of proteins, which causes false positive errors in detection through overestimation of the affinity value. Overcoming this technical issue motivates our research. Polyethylene glycol (PEG) is well known for its ability to reduce the adsorption of biomolecules; hence, it is widely used in various areas of medicine and other biological fields. Likewise, amine functionalized surfaces are widely used for biochemical analysis, drug delivery, medical diagnostics and high throughput screening such as biochips. As a result, many coating techniques have been introduced, one of which is plasma polymerization - a powerful coating method due to its uniformity, homogeneity, mechanical and chemical stability, and excellent adhesion to any substrate. In our previous works, we successfully fabricated plasmapolymerized PEG (PP-PEG) films [1] and amine functionalized films [2] using the plasma enhanced chemical vapor deposition (PECVD) technique. In this research, an amine functionalized PP-PEG film was fabricated by using the plasma co-polymerization technique with PEG 200 and ethylenediamine (EDA) as co-precursors. A biocompatible amine functionalized film was surface characterized by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR). The density of the surface amine functional groups was carried out by quantitative analysis using UV-visible spectroscopy. We found through surface plasmon resonance (SPR) analysis that non-specific protein adsorption was drastically reduced on amine functionalized PP-PEG films. Our functionalized PP-PEG films show considerable potential for biotechnological applications such as biosensors.

• Nutrition Research and Practice
• /
• v.7 no.2
• /
• pp.109-114
• /
• 2013

We compared the preventive capacity of high intakes of vitamin C (VC) and vitamin E (VE) on oxidative stress and liver toxicity in rats fed a low-fat ethanol diet. Thirty-two Wistar rats received the low fat (10% of total calories) Lieber-DeCarli liquid diet as follows: either ethanol alone (Alc group, 36% of total calories) or ethanol in combination with VC (Alc + VC group, 40 mg VC/100 g body weight) or VE (Alc + VE group, 0.8 mg VE/100 g body weight). Control rats were pair-fed a liquid diet with the Alc group. Ethanol administration induced a modest increase in alanine aminotransferase (ALT), aspartate aminotransferase (AST), conjugated dienes (CD), and triglycerides but decreased total radical-trapping antioxidant potential (TRAP) in plasma. VE supplementation to alcohol-fed rats restored the plasma levels of AST, CD, and TRAP to control levels. However, VC supplementation did not significantly influence plasma ALT, AST, or CD. In addition, a significant increase in plasma aminothiols such as homocysteine and cysteine was observed in the Alc group, but cysteinylglycine and glutathione (GSH) did not change by ethanol feeding. Supplementing alcohol-fed rats with VC increased plasma GSH and hepatic S-adenosylmethionine, but plasma levels of aminothiols, except GSH, were not influenced by either VC or VE supplementation in ethanol-fed rats. These results indicate that a low-fat ethanol diet induces oxidative stress and consequent liver toxicity similar to a high-fat ethanol diet and that VE supplementation has a protective effect on ethanol-induced oxidative stress and liver toxicity.

• Bulletin of the Korean Chemical Society
• /
• v.25 no.1
• /
• pp.109-114
• /
• 2004

A sensitive method for quantitation of glimepiride in human plasma has been established using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI/MS/MS). Glipizide was used as an internal standard. Glimepiride and internal standard in plasma sample was extracted using diethyl etherethyl acetate (1 : 1). A centrifuged upper layer was then evaporated and reconstituted with the mobile phase of acetonitrile-5 mM ammonium acetate (60:40, pH 3.0). The reconstituted samples were injected into a $C_{18}$ reversed-phase column. Using MS/MS in the multiple reaction monitoring (MRM) mode, glimepiride and glipizide were detected without severe interference from human plasma matrix. Glimepiride produced a protonated precursor ion ([M+H]$^+$) at m/z 491 and a corresponding product ion at m/z 352. And the internal standard produced a protonated precursor ion ([M+H]]$^+$) at m/z 446 and a corresponding product ion at m/z 321. Detection of glimepiride in human plasma by the LC-ESI/MS/MS method was accurate and precise with a quantitation limit of 0.1 ng/mL. The validation, reproducibility, stability, and recovery of the method were evaluated. The method has been successfully applied to pharmacokinetic studies of glimepiride in human plasma.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.11
• /
• pp.1972-1977
• /
• 2007

Micro plasma has been recently studied to investigate the effects on various cells. We study a micro-plasma produced by a plasma needle that is operated with RF power and its effects on G361 melanoma cells. The micro plasma size ranges from sub-mm to several mm at a few watts of RF power. For the bio-medical treatment, low-temperature plasma is obtained and gas temperature is controlled within several tens of degrees $(^{\circ}C)$ in order not to disturb cell activities. Elementary spectroscopic studies to obtain plasma characteristics are presented for Ar and He plasma with different frequencies of RF power. Also the preliminary results of the micro plasma effects on G361 melanoma cells are presented. It was observed that the irradiation of micro plasma induces cell death through the deprivation of tyrosine phosphorylation in the G361 cells.

• Journal of Pharmaceutical Investigation
• /
• v.34 no.4
• /
• pp.311-317
• /
• 2004

A bioequivalence study of $Gomcillin^{TM}$ capsules (DAEWOONG Pharmaceutical Co., Korea) to $Famoxin^{TM}$ capsules (Dong Wha Pharm. Ind. Co., Korea) was conducted according to the guideline of Korea Food and Drug Administration (KFDA). Twenty four healthy male Korean volunteers received each medicine at the amoxicillin dose of 500 mg in a $2{\times}2$ crossover study. There was a one-week wash out period between the doses. Plasma concentrations of amoxicillin were monitored by a high-performance liquid chromatography for over a period of 8 hours after the administration. $AUC_t$ (the area under the plasma concentration-time curve from time zero to 8 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_t$ and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters indicating that the crossover design was properly performed. The 90% confidence intervals of the $AUC_t$ ratio and the $C_{max}$ ratio for $Gomcillin^{TM}/Famoxin^{TM}$ were $log0.91\;{\sim}\;log1.03$ and $;log0.93\;{\sim}\;log1.10$, respectively. These values were within the acceptable bioequivalence intervals of $log0.80\;{\sim}\;log1.25$. Thus, our study demonstrated the bioequivalence of $Gomcillin^{TM}$ and $Famoxin^{TM}$ with respect to the rate and extent of absorption.