Development Of Textile Structured Biologic Composites Artificial Trachea

Tracheal resection and reconstruction should be performed sometimes due to trauma or tumors, and tracheal prosthesis is preferred especially when the reconstruction of tracheal defects is more than 50mm. Although the research of biocompatible tissue-engineered trachea is still in its initial stages, the perfect integration and development of polymeric sciences and life sciences provide necessary substitutes for tracheal prosthesis.Polymeric biomaterials comprise mainly synthetic and natural materials. The former such as polymers are characteristic of certain mechanical strengths and processing properties, which can provide appropriate scaffolds for cell growth and tissue regeneration. Compared with the former, the latter which possess excellent biocompatibility and biodegradability play a crucial role in inducing and facilitating cell growth and tissue regeneration. The objective of this project is to properly integrate the two kinds of different materials above to develop a new type of biologic composites artificial trachea, whose basic framework is textile fabric with sequential coating of bioactive materials, and to obtain the proper fabrication technology based on the results of experiments.Firstly, after a great deal of investigation and research, the author chose polypropylene(PP) and poly(glycolide-lactide)(PGLA) as the tubular fabric material and the acetic acid solution of Chitosan as the coating material. Polypropylene display superior biomechanical properties while the PGLA fiber is characteristic of controllable biodegradability, and Chitin integrate the excellent biological properties of both Collagen and cellulose. Secondly, based on the ideal characters of artificial trachea, three types of tubular fabric were designed as the stent: woven tubular fabric; plating knitted tubular fabric and completely degradable knitted tubular fabric whichis made of PGLA only.In view of the influence of coating procedure, preferable concentration of the coating solution was selected by evaluating the different coating effect, and it was adopted in the production process of the artificial tracheal samples.Then mechanical experiments were carried out to measure the longitudinal tensile strength and radial supportive strength. Based on the testing results, the different deformation functions of the tubular fabric were obtained and we conclude that the strength indexes vary directly as the material diameter and the arrangement of the PP and PGLA has a prominent influence to the radial supportive strength of the woven artificial trachea. In addition, the degradation property of the tracheal prosthesis was investigated and this provides another important foundation for the fabrication technology of the artificial trachea.Achievements of this research have high value for reference and provide theory foundation for the investigation of tracheal prosthesis. It will accelerate the development of textile technology in medicine field.