• 제목/요약/키워드: Liposomes

검색결과 337건 처리시간 0.022초

INTERACTION OF TENECIN FRAGMENTS WITH LIPOSOMES

  • Park, Myeong-Jun;Cho, Hyun-Sook;Hong, Sung-Yu;Yoon, Jeong-Hyeok;Lee, Keun-Hyeong;Moon, Hong-Mo;Cheong, Hong-Seok
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1996년도 정기총회 및 학술발표회
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    • pp.37-37
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    • 1996
  • Tenecin fragments are antimicrobial and antifungal peptide from Tenebrio molitor with highly positive charged amino acid residues. To elucidate their membrane selectivity and molecular mechanism, various forms of tenecin fragments were synthesized, and their interaction with acidic phospholipid, Gram (+), fungal and human erythrocyte membrane were investigated by ANTS/DPX leakage, membrane binding and fusion assay. (omitted)

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The Formation of Magnetite Nanoparticle in Ordered System of the Soybean Lecithin

  • Li, Tiefu;Deng, Yingjie;Song, Xiaoping;Jin, Zhixiong;Zhang, Ying
    • Bulletin of the Korean Chemical Society
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    • 제24권7호
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    • pp.957-960
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    • 2003
  • A method of preparation of magnetite nanoparticles in ordered systems, as in vesicle and microemulsion, consisting of soybean lecithin and water has been introduced. The size of magnetite grain was controlled by the content of soybean lecithin and size of liposomes in the systems. It was found by experiment that magnetite nanoparticles were formed inside the double layer vesicles. The magnetite nanoparticles were separated by magnetic separation and centrifugation and the dispersion of the magnetite nanoparticles prepared at 10% (w/w) soybean lecithin was particularly stable. The formation of pure magnetite nanoparticles was confirmed by analyses of XRD and electron diffraction pattern.

Haematococcus pluvialis 유래 아스타잔틴의 리포좀 캡슐화가 코스메슈티컬 소재로서의 안정성에 미치는 영향 (Effect of Liposomal Encapsulation of Astaxanthin from Haematococcus pluvialis on Stabilities for Cosmeceuticals)

  • 이정현;김동명;변상요
    • KSBB Journal
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    • 제26권5호
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    • pp.381-385
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    • 2011
  • Studies were made to improve the stability of astaxanthin which has application limitations caused by light and thermal stability problems in spite of its strong anti-oxidant property. Astaxanthin was extracted from Haematococcus pluvialis with supercritical carbon dioxide. Liposomal encapsulation of astaxanthin to improve the stability was made with high pressure homogenizer. The narrow size distribution was observed with astaxanthin liposomes. Tests on light and thermal stabilities resulted that the liposormal encapsulation improved the stability of astaxanthin for cosmeceutical purposes.

CR 2945-Conjugated Liposomes for Targeting of Human Pancreatic Cancer Cells

  • Yoon, Na-Young;Kim, Jin-Seok
    • Journal of Pharmaceutical Investigation
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    • 제34권6호
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    • pp.459-463
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    • 2004
  • CR 2945, a $gastrin/CCK_B$ receptor antagonist, was conjugated to liposome and tested for the targeting of pancreatic cancer cells in vitro. Successful conjugation was confirmed by FTIR and NMR. The size of CR 2945-conjugated liposome was about 500 nm in diameter, with the zeta-potential being -16.5 mV. In vitro anti-cancer activity of this formulation with or without gemcitabine encapsulated was tested on human pancreatic cancer cells, PANC-1. The growth inhibitory effect of gemcitabine-encapsulating CR 2945-conjugated liposome was found to be 10-fold more potent than that of gemcitabine-encapsulating non-conjugated liposome, suggesting that CR 2945 could be used as a potential cancer targeting moiety by conjugating into liposome.

Encapsulation of Bromelain in Liposome

  • Lee, Dong-Hoon;Jin, Bong-Hwa;Hwang, Yong-Il;Lee, Seung-Cheol
    • Preventive Nutrition and Food Science
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    • 제5권2호
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    • pp.81-85
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    • 2000
  • Bromelain has been used as a meat-tenderizing agent in food processing. To increase the availability of bromelain, microencapsulation into liposome was carried out by the dehydration and rehydration method. Small unilamellar vesicles prepared by sonication treatment showed higher encapsulation efficiency (EE) than by the French press method. In the preparation of liposome, the effect of pH and centrifugal force on EE was also investigated and it showed a higher EE at acidic pH than at alkaline pH with centrifugation at 80, 000$\times$g. The actual EEs except unencapsulated bromelain which bound on the outside surface of liposome by electrostatic interaction also were investigated, and the optimal EE was at pH 4.6, at 0.6 of a ratio of bromelain to phosholipid(18.2%, w/w). Release of bromelain from liposomes was stimulated as the temperature increased at neutral pH.

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Conformation and Biological Activity of Mastoparan B and Its Analogs I

  • 박남규;서정길;구희정;이산나무;Gohsuke Sugihara;김광호;박장수;강신원
    • Bulletin of the Korean Chemical Society
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    • 제18권1호
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    • pp.50-56
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    • 1997
  • The mode of action of mastoparan B, an antimicrobial cationic tetradecapeptide amide isolated from the hornet Vespa basalis, toward phospholipid bilayers was studied with synthetic mastoparan B and its analogs with individual Ala instead of hydrophobic amino acids (1-Ile, 3-Leu, 6-Leu, 7-Val, 9-Trp, 13-Val, 14-Leu) in mastoparan B. Mastoparan B and its analogs were synthesized by the solid-phase method. Circular dichroism spectra showed that mastoparan B and its analogs adopted an unordered structure in buffer solution. In the presence of neutral and acidic liposomes, most of the peptides took an α-helical structure. The calcein leakage experiment indicated that mastoparan B interacted strongly with neutral and acidic lipid bilayers than its analogs. Mastoparan B also showed a more or less highly antimicrobial activity and hemolytic activity for human erythrocytes than its analogs. These results indicate that the hydrophobic face in the amphipathic α-helix of mastoparan B critically affect biological activity and helical contents.

Interaction of Mastoparan B and Its Ala-Substituted Analogs with Phospholipid Bilayers

  • 박남규;서정길;구희정;김승호;Sannamu Lee;Gohsuke Sugihara;김광호;박장수;강신원
    • Bulletin of the Korean Chemical Society
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    • 제18권9호
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    • pp.933-938
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    • 1997
  • The interaction of mastoparan B, a tetradecapeptide toxin found in the hornet Vespa basalis, with phospholipid bilayers was investigated. Synthetic mastoparan B and its analogs, obtained by substituting one hydrophilic amino acid (2-Lys, 4-Lys, 5-Ser, 8-Ser, 11-Lys, or 12-Lys) in mastoparan B with Ala, were studied. Mastoparan B and its analogs were synthesized by the solid-phase method. As shown by circular dichroism spectra, mastoparan B and its analogs adopted an unordered structure in buffer solution. All peptides took an α-helical structure, and the α-helical content of its analogs increased in the presence of neutral and acidic liposomes as compared to that of mastoparan B. In the calcein leakage experiment, we observed that mastoparan B interacted more weakly with lipid bilayers in neutral and acidic media than its analogs. Mastoparan B also showed slightly lower antimicrobial activity and hemolytic activity towards human erythrocytes than its analogs. These results indicate that the greater hydrophobicity of the amphiphilic α-helix of mastoparan B by replacement with alamine residues results in the increased biological activity and helical content.

Photoresponsive Nanocontainers with Ordered Porous Channels

  • Cho, Wansu;Kwon, Youngje;Park, Chiyoung
    • Elastomers and Composites
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    • 제54권2호
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    • pp.149-155
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    • 2019
  • Controlled mass transport in response to stimuli is essential for drug carriers. The complexity of the signaling system under physiological conditions has led researchers to develop precise nanocontainers that respond to stimuli in the physiological environment. Owing to several reasons, soft nanocontainers such as liposomes and micelles have been investigated for use as drug delivery systems. However, such carriers often suffer from the undesired leakage of drug molecules. In contrast, inorganic nanocontainers are robust, and their surfaces can be easily functionalized. For example, mesoporous silica nanoparticles equipped with gatekeeper molecules are increasingly being used for the controlled release of drug molecules in response to the desired stimuli. Since the development of the first hybrid nanocontainer comprising molecular machines, multiple versions of such gatekeeper systems featuring significantly improved stability and precise response to stimuli have been reported. In this study, various methods for incorporating photoresponsive nanocontainers with porous channels are developed.

Effects of Chlorhexidine digluconate on Rate of Rotational Mobility of Porphyromonas gingivalis Outer Membranes

  • Jang, Hye-Ock;Eom, Seung-Il;Kim, Jung-Rok;Shin, Sang-Hoon;Chung, In-Kyo;Yun, Il
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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    • pp.134.1-134.1
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    • 2003
  • Tempting to further understanding the biophysical mechanism of action of chlorhexidine, we examined effects of the antimicrobial agent(chlorhexidine digluconate) on rate of rotational mobility of liposomes of total lipids extracted from anaerobic bacterial outer membranes (Porphyromonas gingivalis outer membranes). (omitted)

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효과적인 암 면역치료를 위한 생체재료 연구동향 (Recent Research Trend in Biomaterials for Effective Cancer Immunotherapy)

  • 한준혁;고은진;김준규;박우람
    • 공업화학전망
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    • 제22권6호
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    • pp.2-12
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    • 2019
  • 최근 암 면역치료는 임상연구에서 긍정적인 결과를 보이고 있으며 암 질환의 표준치료법으로 자리 잡아가고 있다. 암 면역치료는 암의 재발과 전이를 획기적으로 개선시킬 수 있다는 이점이 있다. 하지만 전체 암 환자의 15~20%에서만 치료 효과를 보이고 심각한 부작용을 유발할 수 있다는 임상적 한계가 있다. 이러한 문제점들을 개선하기 위해서 기존에 약물전달 또는 조직공학 분야에서 활용되었던 생체재료를 도입하여 면역치료의 효과를 개선하고 부작용은 줄이려는 시도가 활발하다. 본 기고문에서는 효율적인 암 면역치료를 위한 생체재료(나노입자, 리포좀, 미립구, 및 하이드로젤)에 관한 최신 연구동향을 다루고자 한다. 고기능성 생체재료 개발과 종양 면역학 분야의 깊은 이해는 효과적인 암 면역치료제를 개발하는데 있어서 매우 중요하다.