• Food Science and Biotechnology
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• v.14 no.1
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• pp.112-116
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• 2005

Composite films were prepared with soy protein isolate (SPI) and various clay minerals by casting from polymer and clay water suspension. Effects of clay minerals on film thickness, moisture content (MC), tensile strength (TS), elongation at break (E), water vapor permeability (WVP), and water solubility (WS) were tested. Properties including thickness, surface smoothness, and homogeneity of films prepared with organically modified montmorillonite (O-MMT), Wamok clay (W-clay), bentonite, talc powder, and zeolite were comparable to those of control SPI films. TS increased significantly (p<0.05) in films prepared with O-MMT and bentonite, while WVP decreased significantly (p<0.05) in bentonite-added films. WS of most nanocomposite films decreased significantly (p<0.05).

• Biomaterials and Biomechanics in Bioengineering
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• v.2 no.1
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• pp.1-13
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• 2015

Despite recent progresses in nanoparticle-based drug delivery systems, there are still many unsolved limitations. Most of all, a major obstacle in current nanoparticle-based drug carrier is the lack of sufficient drug delivery into target cells due to various biological barriers, such as: extracellular matrix, endolysosomal barrier, and drug-resistance associated proteins. To circumvent these limitations, several research groups have utilized photochemical internalization (PCI), an extension of photodynamic therapy (PDT), in design of innovative and efficient nano-carriers drug delivery. This review presents an overview of a recent research on utilization of PCI in various fields including: anti-cancer therapy, protein delivery, and tissue engineering.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.372-379
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• 2018

The improvement of $NO_x$ reduction by $Ag/{\gamma}-Al_2O_3$ with a hydrocarbon ($n-C_7H_6$) in the early state was investigated in a packed-bed dielectric barrier discharge plasma reactor. The results revealed that the combination of plasma with the catalyst enhanced $NO_x$ reduction efficiency at low operating temperatures, depending on the temperature and specific input energy. To sum up, the poor performance of the catalytic $NO_x$ reduction at low temperatures in the early stage before reaching thermochemical steady state can be greatly compensated for by using the atmospheric-pressure plasma generated in the catalyst bed.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.4
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• pp.395-400
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• 2017

Atopic dermatitis is a chronic inflammatory skin disease caused by a variety of genetic and environmental factors, dysregulation of immunological response, as well as dysfunction of the skin barrier proteins. The purpose of this study is to develop an ELISA kit suitable for evaluating the expression of skin barrier proteins. Proteins were obtained from the skin via AriNo and D-Squame patches. The efficiency of protein collection from the skin, using the Arino patch, was shown to be more effective than using D-Squame; while the efficiency of lysis using 0.1% Triton-X100 was higher than that of other lysis solutions, including 0.1 M Tris-HCL, 0.1% Tween-20, and 5 mM KOH. Recombinant skin barrier proteins, such as filaggrin and involucrin, were produced by molecular biological methods. Monoclonal antibodies against filaggrin and involucrin were produced by immunization of mice, fusion of spleen cells and myeloma cells, as well as a selection of antibody-producing hybridoma cells. The filaggrin expression in the skin of subjects suffering from atopic dermatitis was lower than that in normal mice. Involucrin expression was not altered between normal individuals and subjects with atopic dermatitis. These findings contribute to an elucidation of the importance of the skin barrier protein expression in atopic dermatitis and the development of a diagnostic kit for atopic dermatitis.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.225-235
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• 2019

Cymbopogon citratus (CC) and Perilla frutescens (PF) are known to exert various biological effects. However, their skin hydration and skin barrier effects remain unclear. This study investigated effects of their extracts on skin hydration and skin barrier and analysed the phenolic compounds. effects of these extracts on skin hydration in HaCaT cells showed that Hyaluronic acid production in cells treated with ethanol extracts was higher than that treated with water extracts for both CC and PF. HPLC was used to analyse 19 phenolic compounds in CC and PF ethanol extracts (CCE and PFE). Results revealed chlorogenic acid and p-coumaric acid in CCE and rosmarinic acid and caffeic acid in PFE. Expression levels of hyaluronan synthase 1 (HAS1), HAS2, HAS3, and aquaporin 3 (AQP3), which are related to skin moisturization, and filaggrin and loricrin, which are related to skin barrier were higher in cells treated with CCE than with PFE. CCE and PFE also increased expression of PPAR-a protein involved in skin moisturization and epidermal differentiation in a concentration-dependent manner. As major components of CCE, chlorogenic acid and p-coumaric acid increased PPAR-a protein expression. Thus, CCE and PFE could be used as functional cosmetic materials for skin hydration and skin barrier effects.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.2
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• pp.167-177
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• 2016

This work investigated the decomposition of aqueous anatoxin-a originated from cyanobacteria using an underwater dielectric barrier discharge plasma system based on a porous ceramic tube and an alternating current (AC) high voltage. Plasmatic gas generated inside the porous ceramic tube was uniformly dispersed in the form of numerous bubbles into the aqueous solution through the micro-pores of the ceramic tube, which allowed an effective contact between the plasmatic gas and the aqueous anatoxin-a solution. Effect of applied voltage, treatment time and the coexistence of nutrients such as $NO_3{^-}$, $H_2PO_4{^-}$ and glucose on the decomposition of anatoxin-a was examined. Chemical analyses of the plasma-treated anatoxin-a solution using liquid chromatography-mass spectrometry (LC-MS) and ion chromatography (IC) were performed to elucidate the mineralization mechanisms. Increasing the voltage improved the anatoxin-a decomposition efficiency due to the increased discharge power, but the energy required to remove a given amount of anatoxin-a was similar, regardless of the voltage. At an applied voltage of 17.2 kV (oxygen flow rate: $1.0L\;min^{-1}$), anatoxin-a at an initial concentration of $1mg\;L^{-1}$ (volume: 0.5 L) was successfully treated within 3 min. The chemical analyses using LC-MS and IC suggested that the intermediates with molecular weights of 123~161 produced by the attack of plasma-induced reactive species on anatoxin-a molecule were further oxidized to stable compounds such as acetic acid, formic acid and oxalic acid.

• Applied Chemistry for Engineering
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• v.24 no.1
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• pp.87-92
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• 2013

Nonthermal plasma hybridized with photocatalysts is proven to be an effective tool to degrade toxic organics in wastewater. In this study, a specially designed dielectric barrier discharge (DBD) plasma system combined with photocatalysts was applied to decompose pestiticides such as dichlorovos, carbofuran and methidathon, which are frequently used in the golf courses and the orange plantations. The degradations of the pesticides in single and coupled systems were evaluated. The single system was used with ozone plasma which consisted of electrons, radicals, ions produced by oxygen gas and air, with and without ultra-violet (UV) irradiation, respectively. The coupled systems utilized the air-derived ozone plasma combined with zinc oxide, titanium dioxide and graphite oxide photocatalyst activated by UV. The graphite oxide was synthesized by a modified Hummer's method and characterized using FTIR spectrometer. It was elucidated that the plasma reaction with graphite oxide (0.01 g/L) brought about almost 100% of degradation degrees for dichlorovos and carbofuran in 60 min, as compared with the performances showed by no catalyst condition. The photocatalyst-hybridized plasma in the presence of UV irradiation was proven to be an effective alternative for degrading pesticides.

• Journal of Plant Biotechnology
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• v.37 no.3
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• pp.283-291
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• 2010

Vaccine is one of the best known and most successful applications of immunological theory to human health and it protects human life through inducing the immune response in systemic compartment. However, when we consider the fact that mucosal epithelium is exposed to diverse foreign materials including viruses, bacteria, and food antigens and protects body from entry of unwanted materials using layer of tightly joined epithelial cells, establishing the immunological barrier on the lining of mucosal surfaces is believed to be an effective strategy to protect body from unwanted antigens. Unfortunately, however, oral mucosal site, which is considered as the best target to induce mucosal immune response due to application convenience, is prone to induce immune tolerance rather than immune stimulation. Since intestinal epithelium is tightly organized, a prerequisite for successful mucosal vaccination is delivery of antigen to mucosal immune induction site including a complex system of highly specialized cells such as M cells. Consequently, development of efficient mucosal adjuvant capable of introducing antigens to mucosal immune induction site and overcome oral tolerance is an important subject in oral vaccine development. In this review, various approaches on the development of oral mucosal adjuvants being suggested for effective oral mucosal immune induction.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.455-462
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• 2014

This work investigated the hydrophobic coating of silicate yellow phosphor powder in the form of divalent europium-activated strontium orthosilicate ($Sr_2SiO_4:Eu^{2+}$) by using an atmospheric pressure dielectric barrier discharge (DBD) plasma with argon as a carrier and hexamethyldisiloxane (HMDSO), toluene and n-hexane as precursors. After the plasma treatment of the phosphor powder, the lattice structure of orthosilicate was not altered, as confirmed by an X-ray diffractometer. The coated phosphor powder was characterized by scanning electron microscopy, fluorescence spectrophotometry and contact angle analysis (CAA). The CAA of the phosphor powder coated with the HMDSO precursor revealed that the water contact angle increased from $21.3^{\circ}$ to $139.5^{\circ}$ (max. $148.7^{\circ}$) and the glycerol contact angle from $55^{\circ}$ to $143.5^{\circ}$ (max. $145.3^{\circ}$) as a result of the hydrophobic coating, which indicated that hydrophobic layers were successfully formed on the phosphor powder surfaces. Further surface characterizations were performed by Fourier transform infrared spectroscopy and X-ray photoelectron spectrometry, which also evidenced the formation of hydrophobic coating layers. The phosphor coated with HMDSO exhibited a photoluminescence (PL) enhancement, but the use of toluene or n-hexane somewhat decreased the PL intensity. The results of this work suggest that the DBD plasma may be a viable method for the preparation of hydrophobic coating layer on phosphor powder.

• Electronics and Telecommunications Trends
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• v.35 no.4
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• pp.53-64
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• 2020

The terahertz (THz) region lies in between the millimeter and infrared spectral bands. A THz wave has the characteristics of non-invasiveness and non-ionization due to low photon energies, while having high penetrability in dielectrics. In addition, since the resonance frequencies of various molecules are included in the THz band, research on the application of spectral analysis and non-destructive testing has been widely studied. Towards this end, the research and development of THz detectors has become increasingly important in order to assess their applications in different areas such as astronomy, security, industrial non-destructive evaluations, biological applications, and wireless communications. In this report, we summarize the operating principles, characteristics, and utilization of various broadband technologies in THz detection devices. Further, we introduce the development status of our Schottky barrier diode technology as one of the broadband THz detectors that can be easily adopted as direct detectors in many fields of applications.