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Multi-layer Blood Tubular Scaffold Fabrication by Electrospinning and Braiding

Author: ZhangJianSong
Tutor: MoXiuMei
School: Donghua University
Course: Materials Science and Engineering
Keywords: P ( LLA - CL ) Electrostatic spinning Nano - fiber membrane Stent Biocompatibility
CLC: R318.08
Type: Master's thesis
Year: 2009
Downloads: 35
Quote: 1
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Abstract

In recent years, the incidence of vascular disease increasingly urgent need for a large number of vascular lesions in clinical alternatives, especially the small-diameter artificial blood vessel of less than 6mm diameter. However, artificial vascular grafts in vivo lack of growth activity, adaptation can not be the case with the host, but also easily lead to embolism. Therefore, using tissue engineering technology to prepare the inner layer complete endothelial coverage, the outer layer to facilitate activity of small-caliber vascular smooth muscle cell growth, in order to achieve a satisfactory compatibility and long-term patency. The topic is based on the considerations in this regard, for the first time using a combination of methods of electro-spinning technology and weaving techniques for preparing composite artificial stent, carried out a series of performance tests and comparison, and ultimately determine the best combination. P (LLA-CL) (50/50) 6% by weight was prepared nanofibers having better fiber morphology and diameter distribution, the average diameter as 450 nm; found by scanning electron microscope (SEM) P (LLA-CL) (75/25 ) P (LLA-CL) (50/50) having a better hydrophilicity and a higher degree of crystallinity, and the porosity is just the opposite; the two woven material prepared porosity of the tubular stent were 65.18% and 64.52%, PGLA slightly higher; temperature 100 ℃, time 10 min was determined to be the best heat setting parameters; infrared spectra peaks corresponding to the position with the characteristic peaks of each group good material; tensile mechanical testing shown by P (LLA-CL) (50/50) prepared fiber membrane having a higher elongation at break than the P (LLA-CL) (75/25), but the fracture stress is low, and the mechanical properties of the tube is superior to film, the mechanical properties of the composite pipe bracket has been very good to strengthen, P (LLA-CL) (75/25) composite pipe stent fracture stress of more than 15 MPa, and P (LLA-CL) (50/50) composite tube stent fracture stress is close to 22Mpa, the former exceeding 360% elongation at break, elongation at break of the latter is reached 420%; biocompatibility experiments that pig hip artery endothelial cells 6wt% and 8% by weight P (LLA-CL) (50/50) nanofiber film is more effective adhesion and proliferation; HE staining images and SEM photos showed good growth morphology of endothelial cells, P (LLA-CL) (50/50) 6 wt% fiber membrane cell behavior is the most prominent, gave the strongest evidence of the MTT assay; animal studies, success stories of the usual rate of blood can be maintained for more than two months laid composite stent broad application prospects a good foundation. In summary, the nano-fiber membranes prepared by the comprehensive evaluation of the performance of the inner spinning solution concentration 6wt% of P (LLA-CL) (50/50), the outer surface of the PLLA nanofibers braid, heat setting temperature of 100 ℃, time 10min, the performance of the chitosan solution coating the composite stent has the advantage, and has good biocompatibility, better applications in tissue engineering prospects.

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CLC: > Medicine, health > Basic Medical > Medical science in general > Biomedical Engineering > General issues > Biomaterial
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