复合万古霉素3D打印聚己内酯支架的制备及体外抗菌效果研究

Preparation of a 3D-printed polycaprolactone composite scaffold loaded with vancomycin and its antibacterial effect in vitro

目的研究复合万古霉素3D打印聚己内酯支架(载万古霉素水凝胶聚己内酯复合支架,简称载药复合支架)制备方法及体外抗菌作用。方法采用3D打印技术制备的聚己内酯(PCL)支架作为骨修复的力学支撑。将负载万古霉素的醛基化透明质酸和羧甲基壳聚糖形成的复合水凝胶(Van@Gel)灌注在3D打印PCL支架的孔隙内,制备兼具抗感染性和促成骨修复的双功能骨再生复合支架。通过拉压力试验机对PCL支架进行抗压强度测试;应用紫外分光光度计测量载万古霉素水凝胶不同时间体外药物释放量;通过定性和定量检测载药复合支架体外抗菌性能。结果力学检测发现PCL支架的弹性模量约为(14.89±0.24)MPa,抗压强度约为2 MPa。载万古霉素水凝胶能在30 d内持续释放抗生素,总释放量约为75.5%。在第4天,万古霉素的释放出现明显的突释现象,释放量约为46.6%。体外抗菌实验证实载药复合支架能有效抑制细菌的生长,孵育12 h后即能形成明显的抑菌圈,20 mg/L时抑菌率为52.89%,80 mg/L时抑菌率达到80.49%。结论3D打印支架具有较强的力学性能,载万古霉素复合支架具有良好的体外抑菌作用。

Objective To explore the preparation and in-vitro antibacterial effect of 3D-printed,vancomycin-loading hydrogel-polycaprolactone composite scaffold(VANCS).Methods Polycaprolactone(PCL)scaffolds prepared by 3D printing were used as mechanical support for bone repair.A composite hydrogel(Van@Gel)generated by vancomycin-loaded aldylated hyaluronic acid and carboxymethyl chitosan was fed into the pores of the 3D printed PCL scaffold to form a composite scaffold that was functionally capable of anti-infection and bone repair.The compressive strength of the PCL scaffold was tested by tensile and compression testing device;the in-vitro drug release of Van@Gel at different time points was measured by an ultraviolet spectrophotometer;the antibacterial effect of the VANCS was measured qualitatively and quantitatively.Results Mechanics testing found that the elastic modulus of the PCL scaffold was about(14.89±0.24)MPa,and the compressive strength,about 2 MPa.Continuous antibiotic-release from Van@Gel lasted up to 30 days,with a total release of about 75.5%.On day 4,the vancomycin release showed an obvious burst accounting for about 46.6%of the total release.In vitro antibacterial study confirmed that the VANCS could effectively inhibit bacterial growth.After a 12 h incubation,formation of a bacteriostatic circle was apparent.The bacteriostatic rate was 52.89%at the dose of 20 mg/L,and 80.49%at the dose of 80 mg/L.Conclusion The 3D printed scaffold in this study exhibits strong mechanical properties.The composite scaffold containing vancomycin offers excellent antibacterial effect in vitro.