Fabrication Of A Tio₂Nanotubes Micro-stripes And Its Biocompatibility

Currently, the implanted medical devices for the treatment of cardiovascular diseases would cause intimal injury at different level, which thereby induces restenosis. Therefore, the study on both enhancing the blood compatibility, endothelial cell compatibility and smooth muscle compatibility of the implant material surface become hot. Meanwhile, in recent years, as the deep research of stem cell differentiation induced by materials, it is found that multi-functional mesenchymal stem cells (MSC) which possess potentially differentiation to vascular cells through regulation inducing in vitro. Thus, it is anticipated to get the path that MSC induced to differentiate into vascular endothelial cells in the surface of the material by tissue engineering principles and methods.In this paper, topology micro stripes titania nanotubes (NANO-TOPO) and micro-stripe graphic titania nanotubes (NANO-GRO) were fabricated by photolithography technology combining anodizing. The titania oxide nanotubes (NANO) and plate titanium (Ti) were used as control samples. The blood compatibility, endothelial cell compatibility, smooth muscle cell compatibility and the MSC behavior regulation by the surfaces were performed. The samples were characterized by scanning electron microscopy (SEM), infrared spectrum analysis (FTIR), X-ray diffraction (XRD) and contact angle measurements. The width and space of the micro-stripes was both3μm, the length of the micro-stripes was about60p.m, and the diameter of the nanotubes ranged from50nm to100nm.Blood compatibility evaluation results displayed that NANO-TOPO and NANO-GRO surface had good blood compatibility, from which NANO-TOPO possessed better blood compatibility.Endothelial cell compatibility evaluation results showed that NANO-TOPO and NANO-GRO surface had significantly better endothelial compatibility.Compatibility evaluation results of smooth muscle cells displayed that NANO-TOPO surface could significantly inhibit the adhesion and proliferation of smooth muscle cells, with significantly better compatibility of smooth muscle cells.Short-term culture results of MSC showed that NANO-TOPO and NANO-GRO surface could significantly reverse the inhibition effect on MSC adhesion and proliferation caused by the nanotubes, promoting MSC proliferation.The long-term induction results showed that NANO-TOPO and NANO-GRO could not only regulate the cell morphology of the MSC, but also effectively control the differentiation direction of the cells:the cells expressed a-SMA positively which was specific marker for smooth muscle cells. The result demonstrated that the construction of NANO-TOPO and NANO-GRO could initially realize the possibility of regulating MSC directed differentiation of smooth muscle cells. The experimental research result provides an effective carrier for constructing bionic vascular endothelial function, and prepared the way for further research.