可降解聚合物抗菌纤维膜的原位制备及性能表征

以二氯甲烷、N,N-二甲基甲酰胺为溶剂,以聚乳酸(PLA)为纺丝纤维基体,添加纳米氧化锌(Zn O)和表面活性剂吐温60,利用高压静电纺丝法,原位制备纳米Zn O/PLA复合纤维膜。所得纤维膜中,Zn O分散均匀,纤维平均直径约300 nm,且表面光滑。纺丝纤维的亲水性随着纳米Zn O的增加而大幅提高,断裂强度和延伸率随纳米Zn O含量的增加呈现先上升后下降的趋势。抗菌能力也呈现一定的Zn O含量依赖性。细胞毒性和细胞黏附实验表明,该抗菌纤维膜具有较好的细胞相容性。

In situ-preparation and properties of doped ZnO biodegradable polymer fibers

The nano-zinc oxide (ZnO, 50nm) doped polylactic acid (PLA) nanofibers were fabricated via in-situ electrospinning technique. In this study, the mixture of dichloromethane (DCM) and n,n-dimethyl formamide (DMF) were pre-prepared for the solvent of PLA, then the nano-zinc oxide particles have been mixed into the solvents mixture. After optimazing the preparation procedure, the ZnO particles were well-distributed in the PLA solvents through observed by TEM. The structure of ZnO/PLA composite nanofibers has been observed by SEM, and the diameter was about 300nm. Meanwhile, the so spun fibers were smooth and uniform without any bead-like structure. The mechanical properties of composite nanofibers have been demonstrated by a tensile test, and the results demonstrated that the breaking strength and elongation rate were increased with the percentage of nano-ZnO. It showed that the addition of nano-ZnO may be an effective way to toughen the PLA nanofibers. Additionally, the hydrophilicity of the compound nanofibers has been recorded through a contact angle apparatus. It showed that the hydrophilicity of compound nanofibers were decreased monotonically with the increasing nano-ZnO content, obviously. Then, the cytotoxicity and the antibacterial properties have also been examined. These results suggested that the ZnO/PLA nanofibers were safe to cells and SEM observation also showed that cells had spread well onto the fiber mats with a high level of cell/scaffold interaction; this was demonstrated by the numerous pseudopodia and cell secretions that emerged. Finally, the ability to antibacterial was investigated through a Bacteriostatic ring experiment which showed that the antibacterial property had a ZnO-concentration dependent manner.