• Title/Summary/Keyword: MODIFIED POLYETHYLENE

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Binding of Vaccine and Poly(DL-lactide-co-glycolide) Nanoparticle Modified with Anionic Surfactant (음이온성 유화제로 수식된 폴리락티드/글리코리드 공중합체 나노 입자와 백신의 결합성)

  • Choi, Min-Soo;Park, Eun-Seok;Chi, Sang-Cheol;Shin, Byung-Cheol
    • Journal of Pharmaceutical Investigation
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    • v.34 no.3
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    • pp.177-183
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    • 2004
  • Recently, studies on intranasal mucosa delivery of influenza vaccine have been actively developed because of lack of pain and ease of administration. We studied on preparation of nanoparticle delivery system using biodegradable polymer as a poly(DL-lactide-co-glycolide) (PLGA) and their binding characteristics with vaccine. Three kinds of PLGA nanoparticles were prepared by spontaneous emulsification solvent diffusion (SESD) method using sodium dodecyl sulfate and sodium laurate as an anionic surfactant and Lutrol F68 (polyethylene glycol-block-polypropylene glycol copolymer) as a nonionic surfactant. The 5-aminofluorescein labeled vaccine was coated on the surface of nanoparticles by ionic complex. The complexes between vaccine and nanoparticles were confirmed by change of the size. After vaccine coating on the surface of anionic nanoparticles, particle size was increased from 174 to 1,040 nm. However the size of nonionic nanoparticles was not more increased than size of anionic nanoparticles. The amount of coated vaccine on the surface of PLGA nanoparticles was $14.32\;{\mu}g/mg$ with sodium dodecyl sulfate, $12.41\;{\mu}g/mg$ with sodium laurate, and $9.47{\mu}g/mg$ with Lutrol F68, respectively. In conclusion, prepared nanoparticles in this study is possible to use as a virus-like nanoparticles and it could be accept in the field of influenza vaccine delivery system.

Effect of Storage Temperature, Time and Natural Additives on the Changes in Flavor of Lentinus edodes (저장온도, 시간 및 천연첨가제가 표고버섯의 향 변화에 미치는 영향)

  • Han, Kee-Young
    • Culinary science and hospitality research
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    • v.21 no.1
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    • pp.235-249
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    • 2015
  • This study was carried out to investigate the flavor changes of Lentinus edodes at different storage temperatures, time and natural additives using an electronic nose with six metal oxide sensors. To preserve good quality of modified atmosphere packaged Lentinus edodes, Four natural additives(Artemisia princeps, Artemisia capillaries, green tea, and activated charcoal) were used. The mushrooms were packaged in polyethylene films with each treatment and were stored at 5, 10 and $20^{\circ}C$. Increase in storage temperature and storage time decreased the ratio of resistance in the electronic nose as well as first principal component scores. In addition, indicating quality of mushroom reduced at high temperature and long storage time. The results of the electronic nose and the principal component analysis(PCA) in the mushrooms with Artemisia princeps and Artemisia capillaries that were stored at $5^{\circ}C$, and green tea and activated charcoal which were stored at $10^{\circ}C$ showed the good effects to maintain the freshness along with reducing off-flavor. However, there were no differences between control and treatment groups at $20^{\circ}C$.

The Micrometeorological Requirements for the Culture of Ginseng (Panax sp.) (인삼 (Panax sp.) 재배를 위한 미세기상조건)

  • Proctor John T. A.
    • Proceedings of the Ginseng society Conference
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    • 1988.08a
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    • pp.129-132
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    • 1988
  • Ginseng is cultivated in Korea. Japan. China. the Soviet Union and North America. Studies of the macroclimate of each of these producing areas shows that ginseng has certain requirements for production. In each producing area the microclimate is modified in different ways. Comparisons of recent research data from North America. Korea and China is presented in order to define. more precisely. the various microclimate requirements for ginseng production. These include studies of light interception as influenced by different shade materials. In North America. wood. woven black polypropylene and knitted polyethylene shade are used. whereas in China. dried grasses are bound together in layers with wire and polyvinylchloride is inserted between the layers. The influence of these various shade materials in terms of crop grow1h and root yield are presented. The major effect of temperature seems to be on root growth. During much of the growing season optimum temperatures for root grow1h are not reached. Growth analysis data for different age plants are being used to show the effects of different soil temperature regimes on distribution of dry matter between the shoot and root.

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Electrochemical Properties of Core-Shell Polyolefin Nonwoven Fabric Modified with Sulfonic Acid Group (술폰산기를 갖은 코아-쉘형 폴리올레핀 부직포의 전기화학적 성질)

  • Choi, Seong-Ho;Zhang, Yu-Ping;Shon, Sang-Ho;Lee, Kwang-Pill
    • Analytical Science and Technology
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    • v.17 no.1
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    • pp.60-68
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    • 2004
  • The core-shell polyolefin nonwovon fabric (PNF), wherein the PNF comprises at least about 60% of polyethylene having a melting temperature at ${\sim}132^{\circ}C$ and no more than about 40% of second polypropylene having a lower melting temperature at ${\sim}162^{\circ}C$. The sulfonic acid group for battery separators were prepared by radiation-induced grafting of styrene onto PNF and by the subsequent sulfonation of polystyrene graft chains. The sulfonated PNF was characterized by XPS, SEM, DSC, TGA and porosimeter. The electrochemical properties such as electrolyte retension, electrical resistance, and transport number of the $K^+ions$ were evaluated after sulfonation. It was found that the electrolyte retension increased, whereas the electrical resistance decreased with increasing sulfonic acid content. The transport number of $K^+$ in PNF with sulfonic acid of 0.22 ~ 3.60 mmol/g was to be 0.90 ~ 0.93.

Biological Evaluation of Bone Marrow-Derived Stem Cells onto Different Wettability by RT-PCR (역전사 중합효소 연쇄반응을 이용한 표면 적심성에 따른 골수유래 줄기세포의 생물학적 평가)

  • 김은정;박종수;김문석;조선행;이종문;이해방;강길선
    • Polymer(Korea)
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    • v.28 no.3
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    • pp.218-224
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    • 2004
  • The adhesion and proliferation of mammalian cells on polymeric biomaterials depend on the surface characteristics such as wettability, chemistry, charge and roughness. In order to recognize the correlation between the adhesion and proliferation of human bone marrow derived stem cells (BMSCs) and surface property, radio frequency generated plasma treatment on low density polyethylene (LDPE) has been carried out. The modified LDPE surfaces were characterized by measuring the static water contact angle. The adhesion and proliferation of cells on LDPE films were characterized by cell counting and reverse transcription-polymerase chain reaction (RT-PCR). The water contact angle of the film surface decreased with plasma treatment time. Proto-oncogenes (c-myc, c-fos) and tumor suppressor gene (p153) showed maximum expression with contact angle of 60 ∼ 70$^{\circ}$ range of LDPE film. By cell counting, we confirmed that the rate of cell proliferation appeared the higher on the film surface of the contact angle of 60∼70$^{\circ}$ We concluded that the surface wettability is an important role for the growth and differentiation of BMSCs.

Surface Modification of Polymer Films by Vapor Phase Photografting of Functional Monomers (기상 UV 그라프트 반응에 의한 고분자 필름의 표면 개질)

  • Oh, Seung Hee;Oh, Se Heang;Lee, Jin Ho
    • Journal of Adhesion and Interface
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    • v.1 no.1
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    • pp.23-29
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    • 2000
  • Surface modification of hydrophobic polymeric materials to be hydrophilic or to have specific functional groups is of great importance for a diversity of applications of the materials. In this study, polyethylene (PE) film surfaces were modified by vapor phase photografting of hydrophilic vinyl monomers with different functional groups. The functional monomers were introduced on PE films by introducing the monomers in vapor phase using a vapor phase photografting apparatus designed by our laboratory. Functional monomers used were acrylic acid (negatively chargeable), acrylamide and allylalcohol (neutral), and allylamine and N,N-dimethyl aminopropyl acryamide (positively charged). The functional monomer-grafted PE film surfaces were characterized by the measurement of water contact angles and the attenuated total reflectance Fourier-transform infrared spectroscopy. The vapor phase photografting seems to be effective means for introduction of various functional groups onto polymeric substrates.

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Solubilization of Quercetin , and Permeability Study of Quercetin and Rutin to Rabbit Duodenal Mucosa (퀘르세틴의 가용화 , 퀘르세틴 및 루틴의 토끼 십이지장 점막 투과성)

  • Chun, In-Koo;Seo, Eun-Ha
    • YAKHAK HOEJI
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    • v.42 no.1
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    • pp.59-69
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    • 1998
  • To increase the solubility of quercetin, which is a practically insoluble flavonoid of Ginkgo biloba leaf, the effects of nonaqueous vehicles. Their cosolvents, water-sol uble polymers and modified cyclodextrins (CDs) were observed. Polyethylene glycols, diethyleneglycol monoethyl ether, and their cosolvents with water showed a good solvency toward quercetin. Also the aqueous solutions of povidone, copolyvidone and Cremophor RH 40 was effective in solubilizing quercetin. Complex formation of quercetin with ${\beta}$-cyclodextrin (${\beta}$-CD), dimethyl-${\beta}$-cyclodextiin (DMCD), 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD) and ${\beta}$-cyclodextrin sulfobutyl ether (SBCD) in water was investigated by solubility method at $37^{\circ}C$. The addition of CDs in water markedly increased the solubility of quercetin with increasing the concentration. AL type phase solubility diagrams were obtained with CDs studied. Solubilizaton efficiency by CDs was in the order of SBCD >> DMCD > HPCD > ${\beta}$-CD. The dissolution rates of quercetin from solid dispersions with copolyvidone, povidone and HPCD were much faster than those of drug alone and corresponding physical mixtures, and exceeded the equilibrium solubility (3.03${\pm}1.72{\mu}$g/ml). The permeation of quercetin through duodenal mucosa did not occur even in the presence of enhancers such as bile salts, but the permeation was observed when the mucus layer was scraped off. This was due to the fact that quercetin had a strong binding to mucin ($58.5{\mu}$g/mg mucin). However rutin was permeable to the duodenal mucosa. The addition of enhancer significantly increased the permeation of rutin in the order of sodium glycocholate.

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Preservation of Strawberries and Cucumbers Packaged by Low density polyethylene film impregnated with antimicmbial agent, Scutellariae baicalensis extract (황금추출물을 함유한 항균성 포장필름을 이용한 딸기와 오이의 저장효과)

  • 정순경;조성환
    • Food Science and Preservation
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    • v.9 no.3
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    • pp.271-276
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    • 2002
  • To develop a wrapping film, which suppresses the microbial decay through the storage and prolongs the selflife of fruits and vegetables, the antimicrobial packaging films were prepared and applied to the preservation of strtwberries and cucumbers. Low density polyethylene(LDPE) film of 50㎛ thickness was faricated with 1% of Scutellariae baicalensis extract. The LDPE film impregnated with Scutellariae baicalensis extract showed antimicrobial activity on the disk test against Bacillus cereus, Escherchia coli and Fusarium sp.. The antimicrobial film changed the color and light transmittance, but did not affect heat shrinkage, mechanical tensile strength and wattability. Strawberries and cucumbers were separately wrapped with packaging films in the state of closely-adhered packaging as well as modified atmosphere packaging(MAP). The wrapped strawberries and cucumbers were stored for 21 days at 5$\^{C}$ and for 40 days at l0$\^{C}$, respectively. For the packaged strawberries and cucumbers at 5$\^{C}$ and 10$\^{C}$, the LDPE film impregnated with Scutellariae baicalensis extract showed the reduced growth of total aerobic bacteria, molds and yeasts and did not give any negative effect on other quality attributes during storage in comparison with conttrol film without any additive.

Comparative Quality Evaluation of King Oyster Mushroom as Affected by Unit Packaging Method during Simulated Export Shipment (큰느타리버섯의 모의 수출운송과정에서 소포장 적용에 따른 품질변화 비교)

  • Woo, Seong-Min;Park, Youn-Moon;Park, Se Won
    • Horticultural Science & Technology
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    • v.31 no.2
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    • pp.186-193
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    • 2013
  • Potential of consumer unit packaging was investigated for quality maintenance during export simulation in king oyster mushrooms (Pleurotus eryngii). Mushrooms were harvested in late May, precooled to $4^{\circ}C$ within 6 hours, and then packaged for shipping in two ways: 2 kg bulk packaging in a polyethylene (PE) bag or three types of unit packaging methods such as 400 g in polypropylene film bag (PPB), 200 g on styrofoam tray + PE shrinkage film wrapping (STW), and 200 g in polyethylene terephthalate (PET) containers (PETC). For local distribution of bulk-packaged commodity, mushrooms were sorted again and packaged into 3 consumer units in the same way as for the initial shipping packages. Simulation of refrigerated container shipping was performed in a walk-in type pilot storage at $0.5^{\circ}C$ for 5 weeks, while local marketing simulation was carried out on the shelf at $7^{\circ}C$ for 7 days. During the shipment simulation, creation of modified atmosphere (MA) was substantial in 2 kg bulk packages with low $O_2$ below 2% and high $CO_2$ over 15% whereas, in PPB and PETC unit packages, relatively higher $O_2$ concentrations were observed. On the shelf at $7^{\circ}C$, $CO_2$ concentrations rapidly increased in PPB and PETC packages despite the short marketing period. Overall marketability evaluated by off-flavor, browning, and texture rating was maintained at excellent level when 2 kg bulk packaging in PE or unit packaging in PPB and PETC were used for shipment. In contrast, establishment of MA was very slight in STW packages during shipment and local distribution resulting in poor quality after export simulation. The results suggested that shipment using adequate consumer unit packaging is more practical and economically beneficial than using bulk packaging in the export program consisting of 5-week shipment and 7-day local distribution.

Surface and Chemical Properties of Surface-modified UHMWPE Powder and Mechanical Properties of Self Curing PMMA Bone Cement Containing UHMWPE Powder I. Effect of MMA/Xylene Contents on Surface Modification of UHMWPE (표면개질된 초고분자량 폴리에틸렌 분말의 표면과 화학적 특성 및 이를 함유하는 상온 경화용 폴리(메틸 메타크릴레이트) 뼈 시멘트의 기계적 특성 I. 메틸 메타크릴레이트/자일렌 함량에 따른 초고분자량 폴리에틸렌의 표면 개질 효과)

  • 양대혁;윤관희;김순희;이종문;강길선
    • Polymer(Korea)
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    • v.28 no.1
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    • pp.77-85
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    • 2004
  • It has been widely used ultra high molecular weight polyethylene (UHMWPE) for the biomaterials due to its excellent mechanical properties and biocompatibility. In the case of blend of UHMPE with another polymeric biomaterials, however, UHMWPE might have low blend compatibility due to surface inertness. In this study, in order to improve the mechanical properties of poly(methyl methacrylate) (PMMA) bone cement by means of the impregnation of UHMWPE powder, we developed the novel surface modification method by the mixture of methyl methacrylate (MMA) and xylene. We investigated the variation of composition of MMA/xylene. It was confirmed by the analysis of Fourier transform infrared-attenuated total reflectance, scanning electron microscope, universal transverse mercator, and digital thermometer. The maximum mechanical strength of surface modified UHMWPE powder impregnated PMMA bone cement compound was observed the ratio of 1 : 1 (v/v%) MMA/xylene. Also its curing temperature decreased from 103 $^{\circ}C$ to 58 ∼ 73 $^{\circ}C$ The mechanism of surface modification of UHMWPE powder by the mixture of MMA/xylene has been proposed.