摘要目的 通过测试氧化石墨烯-壳聚糖复合膜的抗拉强度及其对人牙龈成纤维细胞增殖的影响,探讨其作为新型引导骨组织再生膜的可行性.方法 将氧化石墨烯(graphene oxide,GO)溶液与壳聚糖溶液按比例混合,超声破碎分散,通过自蒸发方法成膜,制备GO占壳聚糖的质量分数分别为0.5％、1.0％、2.0％、4.0％、6.0％、8.0％的复合膜和纯壳聚糖膜.采用力学万能实验机测试各组膜试件(每组样本量为6)抗拉强度.取抗拉强度最大的复合膜组膜试件,用扫描电镜和透射电镜察微观结构,X射线衍射仪分析成分.取抗拉强度最大的复合膜组,重新制备试件浸泡于氢氧化钠溶液中进行去酸处理后测试抗拉强度.从安徽医科大学口腔医学院·口腔医院口腔颌面外科收集拔除的阻生牙上残留的牙龈组织,原代培养人牙龈成纤维细胞(human gingival fibroblasts,HGF),培养至第2代,通过免疫细胞化学法染色进行细胞鉴定,用细胞计数试剂盒检测空白对照组、壳聚糖膜组和抗拉强度最大的复合膜组(每组样本量为5)与HGF共培养24、48 h的细胞计数.结果 加入GO后复合膜的截面呈有序的层状结构,X射线衍射分析显示复合膜中存在GO.复合膜抗拉强度随GO比例增加而增加,GO占壳聚糖的质量分数为4.0％时抗拉强度最大,达(134.8±7.3) MPa,此组复合膜去酸处理后抗拉强度为(144.6±8.1)MPa.培养24和48 h时壳聚糖膜组、复合膜组HGF数量与空白对照组差异均无统计学意义(P＞0.05).结论 GO占壳聚糖的质量分数为4.0％时复合膜抗拉强度最大,且细胞相容性良好.

abstractsObjective To explore the feasibility of graphene oxide (GO)-chitosan (CS) guided bone regeneration composite membrane being used as a new guided bone regeneration (GBR) membrane by testing its tensile strength and its effect on the proliferation of human gingival fibroblasts (HGF).Methods The CS solution and GO solution were mixed in following ratios,ultrasonically crushed and dispersed,and formed into membranes by self-evaporation.Composite membrane with 0.5％,1.0％,2.0％,4.0％,6.0％,8.0％ GO in CS was prepared.The tensile strength of the composite membranes was tested by mechanical universal testing machine (n=6).The microstructure of the composite membrane with the best tensile strength was observed by scanning electron microscopy and transmission electron microscopy.X-ray diffraction was used to characterize the ingredients of the material.A group of samples was prepared again with the proportion of the highest tensile strength composite membrane,and were immersed in a sodium hydroxide solution for acid removal.The tensile strength of the new group of samples was tested.The newly extracted impacted teeth were collected from the Department of Oral and Maxillofacial Surgery,Stomatologic Hospital and College,Anhui Medical University,and the gingival tissues remained on the teeth were taken for primary HGF and were cultured to P2 generation,which were identified by immunocytochemical staining methods.Cell counting kit-8 (CCK-8) was applied to detect cell counts in the blank control group,the pure CS membrane group,and the composite membrane group with the highest tensile strength (n=5) and all groups co-cultured with the HGF for 24 h and 48 h.Results After adding GO,the cross-section of the composite membrane was in an ordered layer structure.X-ray diffraction analysis showed that GO could be found in the composite membrane.The tensile strength increased with the increase of GO ratio.When the mass fraction of GO in CS was 4.0％,the tensile strength reached (134.8±7.3) MPa and the tensile strength reached (144.6±8.1) MPa after deacidification of the composite membrane.The CCK-8 test of HGF showed that there was no significant difference in absorbance between the pure CS membrane group and the GO/CS composite membrane group when they were compared with the blank control group (P＞0.05).Conclusions When the mass fraction of GO in CS is 4.0％,the composite membrane has the best tensile strength.The composite membrane showes good cytocompatibility,which lays a foundation for further in vivo experiments and the development of a new generation of GBR membrane.