共查询到18条相似文献,搜索用时 109 毫秒
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壳聚糖是一种新型高分子功能材料,自身具有优良的生物性能.为克服其溶解性较差等缺陷,扩大其应用范围,常采用物理和化学的手段对壳聚糖改性,以改善其物理、化学性能,本文介绍了自2000年以来国内外关于壳聚糖物理和化学改性方面的最新研究进展,阐释了改性途径以及对改性后所得衍生物的相关表征.主要涉及到壳聚糖的烷基化、酰化以及接枝化改性等途径,并列表比较了以上各种手段的改性效果.本文的下篇<壳聚糖改性技术的新进展Ⅱ.交联化、季铵盐化、羧基化改性以及其低聚糖衍生物>将继续介绍基于壳聚糖的其它改性手段的最新进展. 相似文献
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壳聚糖是一种可再生的天然碱性多糖,具有多种优良的特性。但是,由于壳聚糖本身的溶解性很差,只能溶解在一些稀酸中,这就在一定程度上限制了其进一步的研究与应用。因此,通过修饰改性提高其已有功能、赋予新的功能是壳聚糖重要的研究领域。其中,通过磷酸化或磷酰化改性是壳聚糖改性研究的方向之一。本文综述了在壳聚糖链上引入含磷/膦基团合成壳聚糖含磷衍生物的研究进展;介绍并讨论了壳聚糖含磷衍生物的合成及纯化方法;对壳聚糖含磷衍生物结构、性能及表面形貌的表征进行了详细的阐述;对壳聚糖含磷衍生物的应用进行了总结,并展望了壳聚糖含磷衍生物未来的应用前景。 相似文献
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壳聚糖(CS)和聚乳酸(PLA)具有许多独特的性能,包括可生物降解性、良好的生物相容性,对人体无刺激、无毒,是一种绿色生物医药材料,具备潜在的应用价值。将二者单独用于医药领域优势不是很显著,而聚乳酸改性壳聚糖的产物及其衍生物能够很好地融合二者的优点,改性后能得到综合性能更好的生物医学复合材料。本文从聚乳酸改性壳聚糖的角度,综述了壳聚糖和聚乳酸的性质、改性原因、改性现状、改性产物的性能以及在医药领域的一些应用,重点介绍了改性产物在药物缓释方面的应用,并指出今后改性材料方面应注意的问题和发展趋势。 相似文献
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壳聚糖具有抗菌、抗氧化、增强胶凝特性以及可作为生物活性分子的微型或纳米载体等优点,因此其化学改性和应用近年来受到广泛关注。然而,壳聚糖既不溶于有机溶剂也不溶于水,极大地限制了它的应用。在改性的壳聚糖中,聚乙二醇化壳聚糖不仅能保持壳聚糖的优点,还能提高水溶性,并能有效运输生物活性分子。因此,本文总结了2008-2012年聚乙二醇化壳聚糖作为紫杉醇、阿霉素、5-氟尿嘧啶等小分子载体的最新进展,为今后聚乙二醇化壳聚糖的研究提供有益参考和理论依据。 相似文献
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Shigehiro Hirano 《Macromolecular Symposia》2001,168(1):21-30
A series of novel human‐made functional fibers (biofibers) based on chitin and chitosan are prepared by the wet‐spinning and the post chemical modification of chitosan fiber. The wet‐spinning gives rise to a series of biofibers: chitin, chitosan, chitin‐cellulose, chitosan‐cellulose, chitin‐silk fibroin, chitin‐glycosaminoglycans, chitin‐cellulose‐silk fibroin, chitosan‐tropocollagen, and chitin‐cellulose‐silk fibroin. The post chemical modification of chitosan fiber gives rise to a series of chemically modified fibers: N ‐acylchitosans, N ‐arylidene‐ and N ‐alkylidene‐chitosans, N ‐acetylchitosan (chitin)‐tropocollagen, and chitosan‐transition metal complexes. Some of the current and potential applications of these biofibers are described. 相似文献
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Infrared optical properties and AFM of spin-cast chitosan films chemically modified with 1,2 Epoxy-3-phenoxy-propane 总被引:1,自引:0,他引:1
Nosal WH Thompson DW Yan L Sarkar S Subramanian A Woollam JA 《Colloids and surfaces. B, Biointerfaces》2005,46(1):26-31
Chemical modification of spin-cast chitosan films has been performed. This modification involves the attachment of 1,2 Epoxy-3-phenoxy-propane, commonly known as glycidyl phenyl ether (GPE), to the amine group of the chitosan molecule. Optical properties of modified films have been determined in the infrared region of the spectrum using spectroscopic ellipsometry, and are reported in this paper. Special attention is paid to the infrared region where the index of refraction and extinction coefficients from 750 to 4000 cm(-1) were determined. Difference plots of IR optical data before and after chemical modification were generated to confirm that modification had occurred. Optical modeling of infrared spectroscopic ellipsometry (IRSE) data with respect to chemical bond vibrations has also been performed. This modeling involved curve fitting of resonant chemical bond absorptions using Lorentz oscillators. These oscillator models allow for comparison of modified chitosan to unmodified chitosan. The purpose of this research was to determine infrared optical constants of chemically modified chitosan films This work shows that surface chemistry of biomaterials can be studied quite sensitively with spectroscopy ellipsometry, detecting as little as 100 ng/cm(2) of GPE. 相似文献
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《Journal of Dispersion Science and Technology》2013,34(3-4):489-498
Abstract Chitosan has been investigated as a non‐viral vector because it has several advantages such as biocompatibility, biodegradability, and low toxicity. However, low specificity and low transfection efficiency of chitosan as a DNA carrier need to be overcome prior to clinical trial. In this review paper, chemical modification of chitosan was tried in order to enhance cell specificity and transfection efficiency. Also, chemical modification of chitosan was performed to increase stability of chitosan/DNA complexes. 相似文献
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异相法制备磺酸基取代壳聚糖衍生物 总被引:1,自引:1,他引:0
用3-氯-2-羟基丙磺酸钠与壳聚糖在较低温度下进行非均相反应制备了一系列取代度,结构新颖的改性壳聚糖.实验表明化学改性能极大的提高壳聚糖在水溶液中的溶解性能.研究了不同的反应条件对壳聚糖取代度的影响并用核磁共振表征了它们的结构.反应可在中性、较为温和的条件下进行,通过改变反应时间和反应物比例能有效的控制改性壳聚糖的取代度.改性后的壳聚糖能溶解于中性的水溶液中,浊度实验表明产物具有明显的两性聚电解质特征,其等电点约在pH=5.7.该方法为制备化学改性壳聚糖的一种有效的方法. 相似文献
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The review provides the first generalized and systematized information on the use of click reactions in chitosan chemistry for the preparation of novel polymers with attractive physicochemical and biological properties. The reactions of copper-catalyzed azide—alkyne cycloaddition and the click reactions of chitosan derivatives occurring in the absence of salts or metal complexes are discussed in detail. The data on the pre-click modification of chito-san (i.e., the introduction of azide function, alkyne fragment, highly dipolarophilic moieties, and thiol group into the polymer) are reviewed. Special attention is given to the application of new chitosan derivatives obtained by click modification. 相似文献