• 제목/요약/키워드: chitosan polymer

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Development of New Materials of Ginseng by Nanoparticles

  • Yang, Deok Chun;Mathiyalagan, Ramya;Yang, Dong Uk;Perez, Zuly Elizabeth Jimenez;Hurh, Joon;Ahn, Jong Chan
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2018년도 춘계학술발표회
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    • pp.3-3
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    • 2018
  • For centuries, Panax ginseng Meyer (Korean ginseng) has been widely used as a medicinal herb in Korea, China, and Japan. Ginsenosides are a class of triterpene saponins and recognized as the bioactive components in Korean ginseng. Ginsenosides, which can be classified broadly as protopanaxadiols (PPD), protopanaxatriols (PPT), and oleanolic acids, have been shown to flaunt a vast array of pharmacological activities such as immune-modulatory, anti-inflammatory, anti-tumor, anti-diabetic, and antioxidant effects. In recent years, a number of ginseng and ginsenoside researches have increasingly gained wide attention owing to its unique pharmacological properties. Although good efficacies of ginsenosides have been reported, lack of target specific delivery into tumor sites, low solubility, and low bioavailability due to modifications in gastro-intestinal environments limit their biomedical application in clinical trials. As a result to this major challenge, nanotechnology and drug delivery techniques play a significant role to solve this problematic issue. Thus, we reported the preparation of poly-ethylene glycol (PEG) and glycol chitosan (GC) functionalized to ginsenoside (Compound K and PPD) conjugates via hydrolysable ester bonds with improved aqueous solubility and pH-dependent drug release. In vitro cytotoxicity assays revealed that PEG-CK, and PPD-CK conjugates exhibited lower cytotoxicity compared to bare CK and PPD in HT29 cells. However, GC-CK conjugates exhibited higher and similar cytotoxicity in HT29 and HepG2 cells. Furthermore, GC-CK-treated RAW264.7 cells did not exhibit significant cell death at higher concentration of treatment which supports the biocompatibility of the polymer conjugates. They also inhibited nitric oxide production in lipopolysaccharide (LPS)-induced RAW64.7 cells. In addition to polymer-ginsenoside conjugates, silver (AgNps) and gold nanoparticles (AuNps) have been successfully synthesized by green chemistry using different m. The biosynthesized nanoparticles demonstrated antimicrobial efficacy, anticancer, anti-inflammatory, antioxidant activity, biofilm inhibition, and anticoagulant effect. Special interest on the effective delivery methods of ginsenoside to treatment sites is the focus of metal nanoparticle research.In short, nano-sizing of ginsenoside results in an increased water solubility and bioavailability. The use of nano-sized ginsenoside and P. ginseng mediated metallic nanoparticles is expected to be effective on medical platform against various diseases in the future.

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키티나제에 의한 키토올리고당의 생성활성 규명과 올리고당의 당별 분리 생산 (Action Patterns of Chitinase and Separations of Chitooligosaccharides Produced by Chitinolytic Hydrolysis)

  • 김광
    • KSBB Journal
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    • 제17권1호
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    • pp.100-105
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    • 2002
  • 중합도 n$\leq$10을 갖는 N-아세틸-D-글루코사민(GlcNAc)을 미생물 Serratia marcesce-ns QM B14f6의 최소배지 회분식 발효를 이용하여 키틴 및 키토산을 분해하는 효소 키티나제(1.5 unit/mL) [키토바이아제(3.48 unit/mL)가 포함됨]를 생성시킨다. 효소 반응에 의한 키토올리고당의 생성 활성을 규명하기 위하여 부분적으로 탈아세틸화된 키토산을 효소적 가수분해 반응시킴으로써 생성된 N-아세틸-D-글루코사민과 D-글루코사민의 키토올리고당의 생성 패턴을 확인 조사한다. 이 혼합 올리고머로부터 CM-Sephadex의 컬럼 크로마토그래피에 의하여 당별로 분획시켜 추출한 헤테로 키토 올리고당들을 각각 N-아세틸화하고 이 최종 생성물을 전기투석 장치로서 정제하여 키토올리고 1-7당을 제조하였다. 부분적으로 탈아세틸화 키토산(환원당으로서 2697 mg/mL)을 효소반응에 의해 생성시킨 키토올리고당은 1당으로서 GlcNAc=4.25%, 2당 $(GlcNAc)_2$=4.49%, 3당 $(GlcNAc)_3$=11.1%, 4당 $(GlcNAc)_4$=2.5%, 5당 $(GlcNAc)_{5}$ =0.64%, 6당$(GlcNAc)_{6}$=2.12%, 7당 $(GlcNAc)_{7}$=1.21%가 각각 제조되었다.

Effect of additives on the hydrothermal synthesis of manganese ferrite nanoparticles

  • Kurtinaitiene, Marija;Mazeika, Kestutis;Ramanavicius, Simonas;Pakstas, Vidas;Jagminas, Arunas
    • Advances in nano research
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    • 제4권1호
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    • pp.1-14
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    • 2016
  • Superparamagnetic iron oxide nanoparticles (Nps), composed of magnetite, $Fe_3O_4$, or maghemite, ${\gamma}-Fe_2O_3$, core and biocompatible polymer shell, such as dextran or chitozan, have recently found wide applications in magnetic resonance imaging, contrast enhancement and hyperthermia therapy. For different diagnostic and therapeutic applications, current attempt is focusing on the synthesis and biomedical applications of various ferrite Nps, such as $CoFe_2O_4$ and $MnFe_2O_4$, differing from iron oxide Nps in charge, surface chemistry and magnetic properties. This study is focused on the synthesis of manganese ferrite, $MnFe_2O_4$, Nps by most commonly used chemical way pursuing better control of their size, purity and magnetic properties. Co-precipitation syntheses were performed using aqueous alkaline solutions of Mn(II) and Fe(III) salts and NaOH within a wide pH range using various hydrothermal treatment regimes. Different additives, such as citric acid, cysteine, glicine, polyetylene glycol, triethanolamine, chitosan, etc., were tested on purpose to obtain good yield of pure phase and monodispersed Nps with average size of ${\leq}20nm$. Transmission electron microscopy (TEM), X-ray diffraction, energy dispersive X-ray spectroscopy (EDX), $M\ddot{o}ssbauer$ spectroscopy down to cryogenic temperatures, magnetic measurements and inductively coupled plasma mass spectrometry were employed in this study.

나노 섬유 멤브레인을 기반으로 한 수은(II) 색변화 검출 센서에 대한 총설 (Nanofiber Membrane based Colorimetric Sensor for Mercury (II) Detection: A Review)

  • 방세연;라즈쿠마 파텔
    • 멤브레인
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    • 제31권4호
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    • pp.241-252
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    • 2021
  • 급격한 산업화와 인구수 증가로 인한 환경 수질 오염이 발생하고 있다. 더불어 날씨 패턴의 변화로 인해 빗물이 부족해지자, 폐수를 깨끗한 물로 재활용하기 위한 요구가 나날이 늘어나고 있다. 색변화를 이용한 수중 속 중금속 검출은 아주 간단하고 효과적인 기술이다. 본 논문에는 멤브레인을 이용한 수은 이온 색검출에 대해 자세하게 논의되어 있다. 셀룰로스, 폴리카프로락톤, 키토산, 폴리설폰 등의 멤브레인이 금속 이온 검출을 지지체로서 사용되었다. 지지체로서 사용된 멤브레인들은 나노 섬유를 기반으로 하며 표면적이 크며, 중금속 검출의 활성 부위로 사용하기에 탁월하다. 나노 섬유를 기반으로 한 재료는 에너지, 환경, 그리고 바이오메디컬 연구에서 다양하게 응용될 수 있다. 나노 섬유로 이루어진 멤브레인들은 폴리머에 있는 적용기를 많이 받아들일 수 있으며, 표면적이 넓고 다공성이라는 장점이 있다. 이로 인해 멤브레인의 표면 구조를 변화시키거나 리간드를 섬유 표면에 부착해 나노 입자 결합을 더 쉽게 해준다.

Self-Assembled Nanoparticles of Bile Acid-Modified Glycol Chitosans and Their Applications for Cancer Therapy

  • Kim Kwangmeyung;Kim Jong-Ho;Kim Sungwon;Chung Hesson;Choi Kuiwon;Kwon Ick Chan;Park Jae Hyung;Kim Yoo-Shin;Park Rang-Won;Kim In-San;Jeong Seo Young
    • Macromolecular Research
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    • 제13권3호
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    • pp.167-175
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    • 2005
  • This review explores recent works involving the use of the self-assembled nanoparticles of bile acid-modified glycol chitosans (BGCs) as a new drug carrier for cancer therapy. BGC nanoparticles were produced by chemically grafting different bile acids through the use of l-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). The precise control of the size, structure, and hydrophobicity of the various BGC nanoparticles could be achieved by grafting different amounts of bile acids. The BGC nanoparticles so produced formed nanoparticles ranging in size from 210 to 850 nm in phosphate-buffered saline (PBS, pH=7.4), which exhibited substantially lower critical aggregation concentrations (0.038-0.260 mg/mL) than those of other low-molecular-weight surfactants, indicating that they possess high thermodynamic stability. The SOC nanoparticles could encapsulate small molecular peptides and hydrophobic anticancer drugs with a high loading efficiency and release them in a sustained manner. This review also highlights the biodistribution of the BGC nanoparticles, in order to demonstrate their accumulation in the tumor tissue, by utilizing the enhanced permeability and retention (EPR) effect. The different approaches used to optimize the delivery of drugs to treat cancer are also described in the last section.