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透明质酸与胶原蛋白复合材料的制备及其应用 总被引:5,自引:0,他引:5
随着生物医学及组织工程技术日新月异的发展,各种来源于天然或由人工合成的生物植入被广泛应用于临床治疗。透明质酸和胶原都是较好的生物材料,但在单独使用时,它们的流变学特性粘弹性还不能满足一些特殊治疗的需要。而它的复合物-透明质酸-胶原蛋白复合基质,恰恰填补了这一空白,成为理想的移植物替代品。 相似文献
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透明质酸酶可用于药物渗透剂、动物皮革松散及低分子量的透明质酸制备.实验室前期筛选了一株具有较高透明质酸降解能力的菌株,本研究对其进行了 16S rRNA基因和生理生化反应鉴定,鉴定为弗氏柠檬酸杆菌,但弗氏柠檬酸杆菌来源的透明质酸酶的功能还未见报道.因而,以透明质酸为底物研究其酶学性质,结果表明:该酶最适pH值为5.5,在pH值4.0~8.0下处理1 h可以保持60%以上酶活力;最适温度为50℃,在50℃和60℃下处理1h后剩余60%以上的酶活力.该酶和人源透明质酸酶最适pH相似,但其耐热性更高.因此,本研究挖掘到了新颖的透明质酸酶的资源,并为其开发利用提供了参考价值. 相似文献
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为简化由透明质酸发酵液制备高纯度透明质酸的过程,本实验利用氯苯除去菌体,由乙醇分离得到透明质酸提取物,向提取物中加入由4.2 g/L碳酸氢钠和5.3 g/L碳酸钠以体积比为45:5组成的水溶液及胰蛋白酶进行水解.水解后所得分离物在磷酸二氢钠含量为0.45 g/L,磷酸氢二钠含量为0.05 g/L及氯化钠含量为11.6 g/L的水溶液中溶解,向其中加入3倍体积的95%乙醇,得到沉淀,绝干的沉淀物中透明质酸质量比为98.9%.随后,经活性炭以及透析处理.最终透明质酸质量比为99.996%,相对分子量5.8×105.总回收率96.17%. 相似文献
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转铁蛋白受体抗体的制备,鉴定和性质 总被引:1,自引:0,他引:1
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以双功能螯合剂异硫氰酸苄基乙二胺四乙酸(ITCBE)螯合铅离子,制备得半抗原Pb-ITCBE,然后再分别与载体蛋白KLH或BSA偶联制备得免疫原Pb-ITCBE-KLH与包被抗原Pb-ITCBE-BSA,ITCBE-BSA.用二喹啉甲酸法测3种抗原的浓度,分析半抗原、抗原与载体蛋白的紫外吸收光谱,利用SDS-PAGE对3种抗原的分子量进行鉴定,用三硝基苯磺酸法检测3种抗原中的赖氨酸残基的ε-NH2被半抗原替换的程度,用石墨炉原子分光吸收法检测抗原中铅的含量.研究结果表明,免疫原与包被抗原制备成功,Pb-ITCBE-KLH、Pb-ITCBE-BSA、ITCBE-BSA的浓度依次为6.47± 0.08 mg/ml,6.68± 0.06 mg/ml,5.57± 0.05 mg/ml;抗原与载体蛋白的紫外吸收光谱的特征各不相同;SDS-PAGE的结果显示3种抗原的分子量均不同于各自的载体蛋白;抗原中载体蛋白ε-氨基的替换程度依次为1.86± 0.74 %、55.53± 1.13%、54.19± 1.34%;铅的含量依次为15.64± 0.11 μg/ml,17.33± 0.15 μg/ml,0 μg/ml. 相似文献
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A. Davies J. Gormally E. Wyn-Jones D.J. Wedlock G.O. Phillips 《International journal of biological macromolecules》1982,4(7):436-438
Sodium hyaluronate samples of various molecular weights were prepared and characterized by size exclusion chromatography and dilution viscometry. Densitometry was used for determination of the densities of sodium hyaluronate solutions and the results expressed as partial specific volumes in the respective solvents. Solution adiabatic compressibilities were measured. Hydration parameters of sodium hyaluronate were consequently determined and the values obtained discussed in relation to existing hydration models for sodium hyaluronate in water. 相似文献
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几丁聚糖和透明质酸钠对血管内皮细胞增殖的影响 总被引:1,自引:0,他引:1
目的:比较几丁聚糖和透明质酸钠对血管内皮细胞增殖的影响。方法:用含不同浓度的几丁聚糖和透明质酸钠的培养液对血管内皮细胞(EV304)进行培养,以四唑盐比色法测细胞增殖,并用流式细胞仪测定细胞周期。结果:几丁聚糖在≥0.1mg/ml时促进血管内皮细胞的增殖,透明质酸钠对血管内皮细胞的增殖有抑制作用,几丁聚糖可使细胞周期中G1期比例下降,而透明质酸钠使细胞周期中G1期比例上升。结论:几丁聚糖促进血管内皮细胞的增殖,而透明质酸钠对血管内皮细胞的增殖有抑制作用。 相似文献
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D.J. Wedlock G.O. Phillips A. Davies J. Gormally E. Wyn-Jones 《International journal of biological macromolecules》1983,5(3):186-188
Freeze drying of sodium hyaluronate causes free radical induced depolymerization of the polysaccharide which may be inhibited by such free radical scanvengers as Cl?, I?, alcohols and sugars. The free radical process is probably induced by mechanical stress factors. Such effects are important in freeze drying of all biopolymer solutions. 相似文献
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Structural data for complexes of hyaluronic acid and 3d metals(II) of the fourth group of the periodic table are lacking. A combined QM/MM method was used to solve the structure of the first coordination sphere around the cobalt(II) ion. Some available experimental data were compared with the results obtained via computation and were found to be in good agreement. Our results open the way for using molecular modeling to solve the structure of other metal(II) hyaluronates. 相似文献
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以制备高产量的透明质酸酶为出发点,利用5 L发酵罐对球形节杆菌A152发酵生产透明质酸酶的条件进行优化,并对其发酵动力学模型进行研究。研究结果表明,转速400 r/min、通气量3.5 L/min时,生物量和透明质酸酶酶活力最优,分别为5 g/L、16.4 U/mL;同时对发酵过程中菌体生长、产物生成及基质消耗的规律进行研究,应用Logistic方程、Luedeking-Piret方程和底物消耗的物料平衡方程建立了球形节杆菌Arthrobacter globiformis A152发酵过程的动力学模型,并通过MATLAB软件进行最优参数估计和非线性拟合。模型的计算值与实验值能较好地拟合,表明所建的模型能较好地反映发酵过程,可为发酵过程的在线控制和预测提供理论基础。 相似文献
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Michela Ombelli Lauren Costello Corinne Postle Vinod Anantharaman Qing Cheng Meng Russell J. Composto 《Biofouling》2013,29(5):505-518
Adsorption of bovine serum albumin (BSA) and fibrinogen (Fg) was measured on six distinct bare and dextran- and hyaluronate-modified silicon surfaces created using two dextran grafting densities and three hyaluronic acid (HA) sodium salts derived from human umbilical cord, rooster comb and Streptococcus zooepidemicus. Film thickness and surface morphology depended on the HA molecular weight and concentration. BSA coverage was enhanced on surfaces in competitive adsorption of BSA:Fg mixtures. Dextranization differentially reduced protein adsorption onto surfaces based on oxidation state. Hyaluronization was demonstrated to provide the greatest resistance to protein coverage, equivalent to that of the most resistant dextranized surface. Resistance to protein adsorption was independent of the type of HA utilized. With changing bulk protein concentration from 20 to 40 μg ml?1 for each species, Fg coverage on silicon increased by 4x, whereas both BSA and Fg adsorption on dextran and HA were far less dependent on protein bulk concentration. 相似文献
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P. Månsson Ö. Jacobsson K.A. Granath 《International journal of biological macromolecules》1985,7(1):30-32
The molecular weight of Na- and K-hyaluronate has been determined by low angle laser light scattering (LALLS) technique. Two preparations of hyaluronate from rooster comb () were investigated. The LALLS was carried out both in a static mode and on the effluent from a column filled with porous gel. In contrast to Sheehan et al.1, no significant difference was found in the molecular weight of viscosity of Na- and K-hyaluronate in 2.0 M salt solutions 相似文献
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Abstract Treatment of Pseudomonas aeruginosa cells with the non-metabolizable polysaccharide hyaluronate led to a strong increase in extracellular lipase activity. Alteration of the cell surface either by treatment with the chelator EDTA or by selecting for phage-resistant mutants significantly altered the bacterial response to hyaluronate. Binding of 14 C-labeled hyaluronate to the bacteria was shown to depend on polysaccharide concentration and on cell number. Cell-free exolipase interacted with chemically cross-linked hyaluronate. The results suggested an interaction between hyaluronate and the cell surface of P. aeruginosa as a prerequisite for the polysaccharide to be effective. 相似文献
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Katsukiyo Sakurai Kyousuke Miyazaki Yoh Kodera Hiroyuki Nishimura Masao Shingu Yuji Inada 《Glycoconjugate journal》1997,14(6):723-728
Superoxide dismutase (SOD) from bovine erythrocytes was conjugated with sodium hyaluronate (HA) with a mean molecular weight
of 106 to have greater anti-inflammatory activity in vivo. Amino groups of SOD were coupled with carboxyl groups in the hyaluronate
molecule using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide. The HA-SOD conjugate was composed of 1.5 mol of SOD molecule
per 1 mol of hyaluronate on the average, and retained 70% of the activity of unmodified SOD. The conjugate was essentially
non-immunogenic in mice, and exhibited much higher anti-inflammatory activities than HA or SOD in models of inflammatory diseases
such as ischemic oedema of the foot-pad in mice, carrageenin-induced pleurisy and adjuvant arthritis in rats.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
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Hyaluronate purified from all cations by ion exchange chromatography was introduced to the cations sodium, potassium and calcium in a controlled way. The conformations formed in the presence of these ions were studied as a function of ionic strength, hydrogen ion activity, humidity and temperature using X-ray fibre diffraction. In sodium hyaluronate above pH 4.0 a contracted helix is found which approximates to a four-fold helix with an axial rise per disaccharide of 0.84 nm. There is no requirement for water molecules in the unit cell as the Na+ can be coordinate by the hyaluronate chains alone. On crystallizing hyaluronate below pH 4.0 an extended 2-fold helix with an axial rise per disaccharide of 0.98 nm is formed. In the presence of potassium above pH 4.0 a conformation similar, but not identical, to that of sodium was found where the helix backbone is again four-fold with an axial rise per disaccharide h=0.90 nm. To maintain the coordination of the potassium ion, four water molecule/disaccharide are required and on removal of these the conformation is destabilized going to a new helix where n = 4 and h = 0.97 nm. Below pH 4.0 the conformation is a contracted 4-fold helix with h = 0.82 nm. In this structure two antiparallel chains intertwine to form a double helix. The packing of the double helical units is stabilized by water molecules, the unit cell requiring 8 water molecules/disaccharide. Formation of the calcium hyaluronate complex above pH 3.5 yields a three-fold helix with h = 0.95 nm. The requirement for water in the unit cell to maintain full crystallinity is high, at 9 water molecules/disaccharide; however, on removal of this water, though the crystallinity is disrupted, the conformation remains constant. The acid form of calcium-hyaluronate yields an equivalent conformation to that of sodium under the same condition, i.e. a helix with n = 2, h = 0.98 nm. The presence of small quantities of calcium in what are otherwise potassium or sodium solutions of hyaluronate yield the 3-fold conformation for hyaluronate. Thus calcium has an important role to play in deciding the dominating conformation present in hyaluronate. The variety of conformations yielded by the different cations indicates a subtle interaction between hyaluronate and its environment, in which the balance between the cations will control to some degree the interactions between hyaluronate chains and thus affect the mechanical properties of the matrix which they form. The conformations of individual chains are all stabilized in varying degrees by intra-chain hydrogen bonds. 相似文献