• Title/Summary/Keyword: membrane penetration

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The preparation of skin analogue composition having the liquid crystalline structure and its cosmetic applications

  • Lee, Dong-Kyu;Jeong, Kwan-Young
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.2
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    • pp.215-224
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    • 2013
  • Recently, many cosmetic researchers have been focused on the development of high functional cosmetics including anti-wrinkle and whitening. In these studies, they couldn't afford to pay a deep attention to stable encapsulations for unstable materials and efficient drug deliveries for them. Particularly, in order to show a degree of instant effects as cosmetics, they can't also ignore moisturizing effect enough to satisfy customers just after applying and its maintenance by improving the function of skin barrier as well as above two effects. Therefore, skin analogue systems have attracted considerable attention in the view of structural and compositional similarity to intercellular membrane in stratum corneum. And, some models for skin analogue composition were developed to improve the function of skin barrier, stably encapsulate unstable materials such as retinol, vitamin B, C, E, etc., and control their skin penetration in order to show good effects as cosmetics. In this study, we suggest the new skin analogue model having the compositional similarity as well as conventional structural ones. Our skin analogue membrane(SAM) is mainly composed of ceramide/ cholesterol/phosphatidylcholin/fatty acids and its structural defects are compensated by including cholesterol amphiphile and controlling the ratio of ceramide/cholesterol. It was possible to confirm the formation of skin analogue membrane having highly-densed multilamella structure and compare them according to the change of each ratio with a polarized microscope, X-ray diffraction. More detaily, we observed their structures with a electron microscope(TEM). Finally, we dispersed them in excess of continuous water phase, observed the formation of maltese-cross liquid crystalline and measured the efficiency of drug deliveries and moisturizing effects.

Analysis of Water Penetration through Pores in Spray-applied Waterproofing Membrane Using X-ray CT Images (X-ray CT를 이용한 분무식 방수 멤브레인의 공극 내 물 침투 분석)

  • Choi, Soon-Wook;Kang, Tae-Ho;Chang, Soo-Ho;Lee, Chulho;Choi, Myung-Sik;Kim, Kwang Yeom
    • Journal of the Korean Geosynthetics Society
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    • v.16 no.4
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    • pp.211-219
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    • 2017
  • The spray-applied waterproofing membrane is installed on shotcrete or concrete surface to make impermeable layer with 3-5 mm thick for the purpose of waterproofing. This study aims to determine the internal structure of a spray-applied waterproofing membrane including pores by using X-ray CT technique. Before obtaining X-ray images of the membrane specimens, a waterproof performance test was performed on the membrane specimens with a water pressure of 500 kPa for 28 days. Results show that the movement of moisture is made through micropores. This is based on the fact that the large pores inside the membrane are not saturated and the degrees of saturation of the micropores are high. X-ray image is effective for determining the pore size distribution and whether the membrane with pores contains the water However, it is necessary to pay attention to the determination of water content, since water content may vary depending on the threshold value of X-ray image analysis applied to calculate the water content.

Performance Evaluation System for Construction Environment of the Unified Waterproofing-Root Resistance Membrane layer of the Green Roof System (인공지반 녹화용 방수방근 복합공법의 시공환경을 고려한 성능평가 시스템 연구)

  • Park, Chang-Hwa;Oh, Sang-Keun;Lim, Nam-Gi
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.2
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    • pp.189-199
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    • 2011
  • Installation of a proper root barrier in a green roof system is very important in order to protect the concrete slab of roof and the root penetration in the waterproofing layer. To select the proper root barrier materials and methods, it is necessary to understand the environmental conditions affecting the waterproofing-root barrier system in green roof construction site. Therefore, we suggested as the environmental performance indexes four kinds of performance requirements; root penetration, chemical attack by chemical agent or fertilizer, load impact by soil depth and size of plant, and water pressure. The related four test methods were suggested for the inspection of these performance indexes. In this research, we could suggest for kinds of test methods as standard test methods to evaluate the environmental performance of waterproofing-root barrier for greening roof system.

Structure-Activity Relationships of 9-mer Antimicrobial Peptide analogue of Protaetiamycine, 9Pbw2

  • Kim, Jin-Kyoung;Lee, Eun-Jung;Jung, Ki-Woong;Kim, Yang-Mee
    • Journal of the Korean Magnetic Resonance Society
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    • v.15 no.1
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    • pp.1-13
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    • 2011
  • 9Pbw2 is a 9-mer analog of protaetiamycine derived from the larvae of the beetle Protaetia brevitarsis. Previously, we designed four 9-mer peptide analogues to optimize the balance between the hydrophobicity and cationicity of the peptides and to increase bacterial cell selectivity. Among them, 9Pbw2 has high antibacterial activity without cytotoxicity. The results obtained in previous study suggest that the bactericidal action of 9Pbw2 may be attributed to the inhibition of the functions of intracellular components after penetration of the bacterial cell membrane. In order to understand structure-activity relationships, we determined the three-dimensional structure of 9Pbw2 in 200 mM DPC micelle by NMR spectroscopy. 9Pbw2 has one hydrophobic turn helix from $Trp^3$ to $Arg^8$ and positively charged residues at the N- and C-terminus. This result suggested that positively charged residues from position at the C-terminus in 9Pbw2 may be important for the primary binding to the negatively charged phospholipid head groups in bacterial cell membranes and hydrophobic residues in the middle portion face toward the acyl chains of the hydrophobic lipid in the bacterial cell membrane.

Investigation on the Surface Hydrophobicity and Aggregation Kinetics of Human Calprotectin in the Presence of Calcium

  • Yousefi, Reza;Ardestani, Susan K.;Saboury, Ali Akbar;Kariminia, Amina;Zeinali, Madjid;Amani, Mojtaba
    • BMB Reports
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    • v.38 no.4
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    • pp.407-413
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    • 2005
  • Calcium and zinc binding protein, calprotectin is a multifunctional protein with broad spectrum antimicrobial and antitumoural activity. It was purified from human neutrophil, using a two-step ion exchange chromatography. Since surface hydrophobicity of calprotectin may be important in membrane anchoring, membrane penetration, subunits oligomerization and some biological roles of protein, in this study attempted to explore the effect of calcium in physiological range on the calprotectin lipophilicity. Incubation of human calprotectin ($50\;{\mu}g/ml$) with different calcium concentrations showed that 1-anilino-8-naphthalene sulfonic acid (ANS) fluorescence intensity of the protein significantly elevates with calcium in a dose dependent manner, suggesting an increase in calprotectin surface hydrophobicity upon calcium binding. Our study also indicates that calcium at higher concentrations (6, 8 and 10 mM) induces aggregation of human calprotectin. Our finding demonstrates that the starting time and the rate constant of calprotectin aggregation depend on the calcium concentration.

Preparation of Anion-exchange Membrane for Selective Separation of Urea and Ion (요소(Urea) 및 이온의 선택적 분리를 위한 음이온교환막의 제조)

  • Kim, Byoung-Sik;Kim, Min;Heo, Kwang-Beom;Hong, Joo-Hee;Na, Won-Jae;Kim, Jae-Hun
    • Applied Chemistry for Engineering
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    • v.17 no.3
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    • pp.303-309
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    • 2006
  • In this study, functional anion-exchange membranes have been prepared and characterized to improve the permeation fluxes of the anion and urea for peritoneum dialysis. They were prepared by UV and radiation graft polymerization methods. The separation-membrane prepared by UV graft polymerization showed the highest grafting degree when HEMA and VBTAC were mixed by 1:2 ratio. However, the grafting degree decreased slightly at compositions above the 1:2 ratio because of the disruption of UV penetration caused by build-up of homopolymer. In the case of photo-initiator, the grafting degree increased up to 0.2 wt%, above which it decreased to a small extent. For the two membranes prepared by radiation graft polymerization, the VBTAC/HEMA membrane showed 96% grafting degree for 6 h reaction time and the GMA membrane showed over 100% grafting degree for 2 h reaction time. Anion-exchange membranes were prepared with 113% grafting degree and with DEA and TEA exchange groups. The DEA membrane showed the conversion degree of 70% in 4 h reaction time while the TEA membrane showed 30% in 2 h reaction time. The prepared anion-exchange membranes were permeable to only anions and urea, but not cations.

Preparation of Disulfonated Poly(arylene ether sulfone) Random Copolymer Thin Film Composite Membranes Using a Benign Solvent (친환경용매 기반의 술폰화 폴리아릴렌 에테르 술폰 랜덤 공중합체 Thin Film Composite 제조)

  • Lee, Chang Hyun;McGrath, James E.;Freeman, Benny
    • Membrane Journal
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    • v.24 no.4
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    • pp.292-300
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    • 2014
  • Chlorine-resistant sulfonated poly(arylene ether sulfone) random copolymer (SPAES)-thin film composite (TFC) membranes for desalination are prepared using monoglyme as a selective solvent, which dissolves SPAES, but should be inert to porous polysulfone layer (e.g., Udel$^{(R)}$). Different from formic acid and diethylene glycol used as other selective solvents, monoglyme is environmentally friendly and has much lower boiling temperature. After a pretreatment of Udel$^{(R)}$ support film in isopropyl alcohol-glycerine mixture to minimize pore penetration leading to fairly reduced water flux, coating of SPAES solution in monoglyme onto the support and stepwise drying processes are conducted for defect-free TFC formation. The transport behavior through SPAES-TFC membranes is observed, correlating with the effects of sulfonation level, protonation, and physical and chemical crosslinking of SPAES selective layers.

Development of Dermal Transduction Epidermal Growth Factor (EGF) Using A Skin Penetrating Functional Peptide (피부투과 기능성 펩타이드를 이용한 경피투과성 상피세포성장인자의 개발)

  • Kang, Jin Sun;La, Ha Na;Bak, Sun Uk;Eom, Hyo Jung;Lee, Byung Kyu;Shin, Hee Je
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.45 no.2
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    • pp.175-184
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    • 2019
  • The epidermal growth factor (EGF) has a intrinsic function of inducing growth and proliferation of cells through interacting with cell membrane receptors in human epidermis and dermis layer. These functions of EGF are used as a main ingredient for wound healing medicines and anti-aging cosmetics. As a cosmetic ingredient, the EGF has a problem in exhibiting its natural efficacy due to the lack of the ability to penetrate through the stratum corneum, which is known as the skin barrier. In this study, a recombinant human epidermal growth factor ($MTD_{151}-EGF$) fused with the macromolecule transduction domain $(MTD)_{151}$ with the skin penetration ability was developed to improve the skin penetration efficiency of the EGF. Expression of $MTD_{151}-EGF$ was performed in E. coli transformed with a vector encoding the $MTD_{151}-EGF$ gene and then purified. The purified $MTD_{151}-EGF$ was evaluated using cell proliferation assay, cytotoxicity test and skin penetration test by franz diffusion cell assay and artificial skin. Cell proliferation activity of $MTD_{151}-EGF$ purified to high purity of 99% or above was equivalent to the EGF or better, and cytotoxicity was not observed. In addition, the $MTD_{151}-EGF$ showed an excellent penetration efficiency compared to the EGF in the skin penetration test with EGF and $MTD_{151}-EGF$ labeled by FITC in an artificial skin penetration model. Based on the quantitative analysis of the penetrating substance using franz diffusion cell assay, the amount of penetration was about 16 times more than that of EGF. These results can be regarded as an effective alternative to improve the existing physical transdermal penetration method related to the use of various active ingredients for cosmetics.

Rat Skin Permeation Characteristics of L-cystein to Common Permanent Wave Drug In Vitro (상용 퍼머넌트 웨이브 약제인 L-cystein의 랫드 피부 투과 특성)

  • 김용렬;윤철훈;김낙주
    • Journal of Environmental Health Sciences
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    • v.27 no.4
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    • pp.73-78
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    • 2001
  • Hair will be persuit of beautifulness of human being in various permanent wave by many kinds of its drugs. Skin is based upon the hair which enroll the body of high living animals and have multiple membrane structure In this study used rat the effects of commercial permanent wave products to skin which are composed with L- cysteine and bases Results are as follow: the content of penetration 4 hors later with steady state and no significant changeable after 20 hours later. In cysteine groups, lag time and permeability coefficient of healthy skin is 2.22hr and 0.13$\mu\textrm{g}$/㎥ hr, lag time and permeability coefficient of old skin is 4.01 hr and 0.108 $\mu\textrm{g}$/㎥ hr . In conclusion of study lag time and permeability coefficient in old skin and wounded skin are faster than healthy skin. We notified that fine rinkle and rash of skin were changeable in the case of treating with permanent wave drugs than normal skin.

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Finite Element Analysis of Axisymmetric Sheet Hydroforming Processes (축대칭 박판 액압성형 공정의 유한요소 해석)

  • Jeong, Y. H.;Lee, S. H.;Keum, Y. T.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.03b
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    • pp.26-29
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    • 1999
  • The sectional forming analysis program for analyzing the hydroforming processes of axisymmetric sheet parts was tleveloped. The rigid-viscoplastic FEM formulation based on membrane theory was derived, wh~cta simi~ltaneously solve force equilibrium as well as non-penetration condition. Hill's non-quadratic normal anisotropic yield theory(1979) was used for material behaviour. For describing the liquid pressure iaction, the flexible tool concept was introduced. Isotropic hardening law was also assumed. To verify the \,alidity of the formulation, the stepped cup forming process as well as the hydrostatic bulging test were \imnlated. Simulation results agreed well with Finckenstein and experimental ones.

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