潜在的细菌纤维素/明胶支架材料的制备

Preparation and Properties of the Dialdehyde Bacterial Cellulose-Gelatin Composite Material

实验在pH 1.0,温度40℃,避光条件下,通过高碘酸钠对细菌纤维素(BC)进行氧化,制得双醛细菌纤维素(DHBC)。然后在温度50℃,p H 6.0,DHBC与不同用量的明胶溶液进行作用制得双醛细菌纤维素/明胶(DB-G)3种复合材料(DB-G5,DB-G10,DB-G15)。通过FTIR谱图分析,DB-G中的CO的伸缩振动吸收峰(1 740 cm-1)消失了,相应地在1 600~1 680 cm-1和1 500~1 550 cm-1出现了典型的酰胺Ⅰ的v(CO)和酰胺Ⅱv(N—H)的红外吸收峰,随着明胶比例增加,吸收峰变宽并发生部分紫移。根据模拟体液(SBF)降解测试结果,DHBC及DB-G表现出了良好的可降解性,降解周期为60~90 d。利用比表面积与孔径分布及SEM的测试分析,DB-G5、DBG10、DB-G15的孔径变化呈现出了不断减小的趋势。通过TG/DTG的热解温度测试结果,与BC相比,DHBC热解温度迅速降低,最大失重温度(Tmax)下降80.1℃。然而与明胶发生交联后,热分解稳定性得到明显提高,DB-G的Tmax均大于340℃,但DB-G10和DB-G15的Tmax却不足2℃。抗张强度测试表现出类似的情形,与DB-G10相比,DB-G15没有随着明胶用量的进一步提高。综合分析认为,m(DHBC)∶m(明胶)以1∶10最为合适,即DB-G10可作为一种潜在的组织工程支架材料。

The dialdehyde cellulose （DHBC） was abtained by oxidation of bacterial cellulose （BC） using sodium periodate at 40℃ and pH 1.0 in the dark. And then three kinds of dialdehyde bacterial cellulose-gelatin composites （DB-G） （ DB-GS, DB-G10, DB-G15, respectively） were prepared by reaction of DHBC and gelatin solution at 50℃ and pH 6.0 ± 0.1. By FTIR spectra analysis, the absorption peak of C=O （1 740 cm^-1） of DB-G disappeared,on the contrary,and the typical bands for amide Ⅰ v（ C=O ）appeare at 1 600 -1 680 cm^-1 and for amide Ⅱ v（N-H） at 1 500 - 1 550 cm^-1 ,in which the absorption peaks become hypsochromic shift and widening with the increase of bonding gelatin. According to the degradation test results in the simulated body fluid（SBF） ,DHBC and DB-G showed good biodegradable and the cycle of degradation are basically 60 -90 d. The pore diameter of DB-G5 ,DB-G10 and DB-G15 gradually decrease based on the analysis and test of DB-G by specific surface area, pore diameter distribution and SEM. From the test results of pyrolytic temperature （TG/DTG） ,compared with the BC,the pyrolysis temperature of DHBC fall rapidly ,and the maximum weight loss temperature （ Tmax ） drop 80. 1 ℃. The thermal stability of DB-G was improved considerably after crosslinking with gelatin,in which Tmax were greater than 340 ℃ ,but Tmax of DB-G10 and DB-G15 were less than 2 ℃. Similarly,from tensile strength test,DB-G15 is not further improved than DB-G10 with the increase of gelatin. Comprehensive analysis,the appropriate mass ratio of DHBC and gelatin is 1：10 that DB-G10 can be as a kind of potential biomass-based tissue engineering scaffold material.