改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性观察  

In vivo degradation and histocompatibility of modified chitosan based on conductive composite nerve conduit

作　　者：焦海山[1] 宋悦宁[1] 黄健[1] 李东印[1] 胡毅 JIAO Haishan;SONG Yuening;HUANG Jian;LI Dongyin;HU Yi(Department of Clinical Medicine,Suzhou Vocational Health College,Suzhou Jiangsu,215009,P.R.China;Department of Pharmacy,Suzhou Vocational Health College,Suzhou Jiangsu,215009,P.R.China)

机构地区：[1]苏州卫生职业技术学院临床医学院,江苏苏州215009 [2]苏州卫生职业技术学院药学院,江苏苏州215009

出　　处：《中国修复重建外科杂志》2021年第6期769-775,共7页Chinese Journal of Reparative and Reconstructive Surgery

基　　金：江苏省高等学校自然科学研究项目(18KJD310005);江苏省卫生厅卫生职业技术教育研究室立项课题(J201301);苏州市科技局项目(STSD2011074);江苏省“青蓝工程”资助项目(苏教师[2012]39号)。

摘　　要：目的探讨改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性,以期为组织工程神经构建提供新的支架材料。方法采用微乳液聚合法合成纳米聚吡咯(polypyrrole,PPy),与壳聚糖共混后注入定制的成管模型,冷冻干燥及脱酸后,制成改性纳米PPy/壳聚糖复合材料导管(记作CP导管);再经不同程度乙酰化(乙酰化反应时间分别为30、60、90 min)改性,制备不同乙酰度的CP导管(记作CAP1、CAP2、CAP3导管)。各导管予红外光谱、扫描电镜进行表征,使用四探针电导仪测定电导率。取30只雌性SD大鼠,于背部左、右侧各制备4个皮下筋膜隧道,分别植入上述导管。术后2、4、6、8、10、12周取材,大体观察导管形态及完整性、扫描电镜观察导管微观结构、测量导管降解率,以观察导管体内降解性能;行HE染色及抗巨噬细胞免疫荧光染色,观察导管体内组织相容性。结果经表征证实乙酰化改性后的各导管1 562 cm^(-1)左右的酰胺Ⅱ谱带增强,表示壳聚糖乙酰化改性成功。各导管均具备导电性能,组间电导率差异无统计学意义(P>0.05)。扫描电镜观察示各导管表面相对光滑、结构致密,无明显差异。导管植入体内后,随时间延长均出现一定程度塌陷,其中CAP3导管尤为明显;亦出现不同程度质量丢失,且乙酰化度越高,质量变化越大(P<0.05)。扫描电镜观察示植入12周后材料出现较多孔隙,且随着乙酰化度增加,孔隙呈增大趋势。组织学观察显示术后早期各导管均有较多巨噬细胞、淋巴细胞浸润,随着植入时间延长,淋巴细胞有所减少、成纤维细胞增多、胶原纤维增生明显。结论不同乙酰度的改性壳聚糖基导电复合材料神经导管均有较好的体内生物相容性、可导电、可降解,且降解性与乙酰度相关,有望为组织工程神经构建提供一种新的支架材料。Objective To investigate the in vivo degradation and histocompatibility of modified chitosan based on conductive composite nerve conduit, so as to provide a new scaffold material for the construction of tissue engineered nerve. Methods The nano polypyrrole(PPy) was synthesized by microemulsion polymerization, blended with chitosan,and then formed conduit by injecting the mixed solution into a customized conduit formation model. After freeze-drying and deacidification, the nano PPy/chitosan composite conduit(CP conduit) was prepared. Then the CP conduits with different acetyl degree were resulted undergoing varying acetylation for 30, 60, and 90 minutes(CAP1, CAP2, CAP3 conduits). Fourier infrared absorption spectrum and scanning electron microscopy(SEM) were used to identify the conduits. And the conductivity was measured by four-probe conductometer. The above conduits were implanted after the subcutaneous fascial tunnels were made symmetrically on both sides of the back of 30 female Sprague Dawley rats. At 2, 4,6, 8, 10, and 12 weeks after operation, the morphology, the microstructure, and the degradation rate were observed and measured to assess the in vivo degradation of conduits. HE staining and anti-macrophage immunofluorescence staining were performed to observe the histocompatibility in vivo. Results The characteristic peaks of the amide Ⅱ band around 1 562 cm^(-1) appeared after being acetylated, indicating that the acetylation modification of chitosan was successful. There was no significant difference in conductivity between conduits(P>0.05). SEM observation showed that the surfaces of the conduits in all groups were similar with relatively smooth surface and compact structure. After the conduits were implanted into the rats, with the extension of time, all conduits were collapsed, especially on the CAP3 conduit. All conduits had different degrees of mass loss, and the higher the degree of acetylation, the greater the mass change(P<0.05).SEM observation showed that there were more pores at 12 weeks af

关 键 词：组织工程神经 纳米材料 聚吡咯 壳聚糖 体内降解 组织相容性 神经导管 

分 类 号：R318.08[医药卫生—生物医学工程]