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Analgesis and wound healing effect of chitosan and carboxymethyl chitosan on scalded rats were investigated. A II degree scald model was established in rats, which was subsequently treated with chitosan and carboxymethyl chitosan solution, respectively. The concentration of bradykinin and 5-hydroxytryptophan was detected by assaying enzyme-linked immunosorbent. Healing condition was observed and pathological sections were made to determine the healing effect of chitosan and carboxymethyl chitosan. Results showed that the concentration of bradykinin and 5-hydroxytryptophan peaked at the third hour post-wound in all groups, while the concentration of hydroxyproline peaked at the seventh day post-wound in both chitosan and carboxymethyl chitosan group. The concentration of bradykinin and 5-hydroxytryptophan of carboxymethyl chitosan group was significantly lower than that of control (P < 0.05), while that of chitosan group was similar to that of control (P > 0.05). These findings indicated that carboxymethyl chitosan reduced the concentration of algogenic substances, resulting in analgesia. During the whole recovery process, the hydroxyproline concentration in chitosan and carboxymethyl chitosan group on day 3 and 7 was significantly higher than that of control (P < 0.01); however the significance of such a highness decreased on day 14 (P < 0.05). These findings indicated that chitosan and carboxymethyl chitosan accelerated tissue repair. Meanwhile, chitosan performed better in healing than carboxymethyl chitosan in both decrustation and healing time. In conclusion, carboxymethyl chitosan showed significant analgesis and wound-healing promotion effect, but chitosan only showed wound-healing promotion effect. 相似文献
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高吸水性树脂(Superabsorbent polymers,SAPs)是一种具有优良吸水能力和保水能力的功能高分子材料,因其良好的性能被应用于止血材料、个人卫生产品、干旱地区的农业及林业保水剂、污水处理剂以及生物材料等方面。以天然多糖原料制备新型高吸水性树脂是目前的研究热点之一。本文综述了近年来以海洋生物多糖-壳聚糖为原料制备高吸水性树脂的方法,以及壳聚糖基高吸水性树脂在应用方面的研究进展,并对壳聚糖基高吸水性树脂未来的发展趋势进行了展望。 相似文献
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In this study,the water-based ferromagnetic fluid and magnetic resin made from chitosan and cerium complex(MRCCC) were successfully prepared by using the chemical co-precipitation technique and by the reversed-phase suspension cross-linking polymerization.MRCCC presented uniform and narrow particle size distribution as determined by the Laser Particles Sizer.The Inductively Coupled Plasma-Atomic Emission Spectrometry(ICP-AES),Fourier transform infrared spectroscopy(FT-IR),differential scanning calorimetry(DSC)and X-ray powder diffraction(XRD)study demonstrated that there were iron and cerium existing in MRCCC.The movement of MRCCC under magnetic field proved its magnetic property.The swelling kinetics in water or solutions with different pH indicated that MRCCC could be applied in solutions with pH greater than 1.0.The ferromagnetic fluid particles were stable in MRCCC soaked in solutions with pH >2.0.In view of these results,MRCCC can be used as material for separation,clarification,adsorption,sustained release and hydrolysis activity. 相似文献
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采用负载镧的乙二醇二缩水甘油醚(EGDE)交联壳聚糖微球对含氟水进行吸附处理.该吸附剂的适宜工作条件为:温度30～50℃,pH值7.0,吸附时间30 min.用吸附等温线描述了F-在吸附剂上的吸附平衡,并用动力学模型研究了其吸附动力学机制.结果表明:吸附剂对F-的吸附平衡符合Langmuir吸附等温线和Freundlich吸附等温线,饱和吸附容量为25.7mg·g-1;该吸附剂对F-的吸附既包含化学吸附又包含物理吸附过程,以单分子层的化学吸附为主;吸附动力学符合拟二级动力学方程,吸附过程受化学吸附机理的控制,颗粒内扩散和液膜形成的边界层是其限速步骤. 相似文献
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Chitosan composites and derivatives have gained wide attentions as effective biosorbents due to their low costs and high contents of amino and hydroxyl functional groups. They have showed significant potentials of removing metal ions, dyes and proteins from various media. Chemical modifications that lead to the formation of the chitosan derivatives and chitosan composites have been extensively studied and widely reported in literatures. The aims of this review were to summarize the important information of the bioactivities of chitosan, highlight the various preparation methods of chitosan-based active biosorbents, and outline its potential applications in the adsorption of heavy metal ions, dyes and proteins from wastewater and aqueous solutions. 相似文献
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利用壳聚糖与香草醛反应生成的希夫碱壳聚糖(VCG),通过在其一级羟基上进行交联,制备出壳聚糖缩香草醛螯合树脂(S-VCG)。用红外光谱对其结构进行表征,并研究其对重金属离子Cu2 和Pb2 的吸附特性。结果表明:壳聚糖缩香草醛螯合树脂(S-VCG)对Cu2 的平衡吸附时间4h,最大吸附量的pH≈3.2,吸附量约为43.1mg/g,对Pb2 平衡吸附时间5h,最大吸附量的pH≈4,吸附量约为110mg/g。S-VCG具有较强的抗酸性。 相似文献
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卡托普利生物粘附型缓释胶囊的制备及性能 总被引：1，自引：0，他引：1
为改善卡托普利治疗效果、降低其不良反应并为开发理想的水溶性药物缓释系统提供实验依据和理论基础,采用乳化分散法制备卡托普利/壳聚糖明胶网络多聚物微球,湿法制粒制备Cap生物粘附型缓释胶囊,研究结果表明,Cap生物粘附型缓释胶囊具有良好的胃肠道粘附特性、对胃肠道粘膜的粘附力与处方中羟丙基甲基纤维素(HPMC)用量呈正相关,而与碳酸钙和碳酸镁的用量呈负相关.体外释药试验证明,Cap生物粘附型缓释胶囊与Cap普通片相比具有明显延缓Cap释放作用,药物释放速率与HPMC用量呈负相关,释放动力学模拟结果表明其体外释药行为以希古切(Higuchi)为最佳拟合模型,结果说明,Cap生物粘附型缓释胶囊药物释放行为是扩散和骨架溶蚀协同作用的结果。 相似文献
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生物降解甲壳质的研究 总被引：3，自引：0，他引：3
介绍了利用生物 (主要是微生物 )降解甲壳质的一些研究进展 ,着重讨论了在甲壳质降解中起重要作用的几丁质酶的基本性质和分子生物学特征。指出了生物处理海洋资源 ,开发有用活性物质的应用前景。 相似文献
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