▎ 摘　　要

Graphene is widely used in bone graft materials because of its antibacterial properties, good bone formation, and biocompatibility, as well as its promotion of the proliferation of stem cells. This study explored the value of using graphene composites for treating infected bone defects of open fractures and the influence of carbon nanotubes on postoperative scar formation. A vancomycin-loaded reduced graphene oxide/nano hydroxyapatite (VA-RGO-n HA) composite scaffold was prepared. Aligned carbon nanotubes (ACNTs) were prepared by a chemical vapor deposition method. The VA-RGO-n HA and ACNTs were characterized by scanning electron microscopy. A cell counting method was also used to evaluate the effect of VA-RGO-n HA on the proliferation of bone marrow stromal cells (BMSCs). Fourier transform infrared spectroscopy and thermogravimetric analysis were adopted to analyze the components of the VA-RGO-n HA composite scaffold. Forty healthy male New Zealand White rabbits aged 3 months old were chosen and randomly divided into five groups: RGO group (infected bone defect model+ RGO implantation), RGO-n HA group (infected bone defect model+ RGO-n HA implantation), VA-RGO-n HA group (infected bone defect model+ VA-RGO-n HA implantation), scar control group (scar model+ sterile bandage), and scar model group (scar model+ ACNTs), with each group containing eight animals. Changes of animal inflammatory indexes of infective bone defect and the difference of scar healing time in the different groups were analyzed. The results showed that the number of BMSCs on the composite scaffold loaded with 5% VA was significantly lower than that of RGO-n HA. The numbers of human dermal fibroblasts (HDFs), human smooth muscle cells (HSMCs), human umbilical vein endothelial cells (HUVECs), mouse fibroblast NIH-3T3 cells, and mouse preosteoblastic cells (MC3T3-E1) on the nanotubes were significantly lower than those of control group. The C-reactive protein (CRP) level and white blood cell (WBC) count of the VA-RGO-n HA group were significantly lower than those of the RGO-n HA and RGO groups. The scar healing time of the control group was shorter than that of the model group, indicating that the VA-RGO-n HA composite scaffold prepared in this study had strong antibacterial activity, enabling effective treatment of infected bone defects. ACNTs can effectively inhibit the excessive proliferation of fibroblasts and the formation of hyperplastic scars, providing novel options for the clinical adoption of new carbon nanomaterials.