Morphological changes of pig aorta during freeze-drying procedure / 中国组织工程研究

ABSTRACT

BACKGROUND: The freeze-drying blood vessel is an excellent material for vasotransplantation. However, the reports concerning freeze-drying are few, and the mechanical property changes of freeze-dried blood vessel remains poorly understood. OBJECTIVE: Using micro-CT to explore the morphological changes of blood vessel during procedure of freeze-drying. DESIGN, TIME AND SETTING: A single sample observation was performed at the Institute of Refrigeration and Cryogenics, University of Shanghai for Science and Technology. MATERIALS Fresh pig aorta was obtained from Shanghai Slaughter House. The lyophilizer was produced by SP Industries (USA). TRAPEZIUM LITE texture analyzer was purchased from Shimadzu (Hong Kong) Co., Ltd.METHODS: The differences of mechanical property between fresh aorta and freeze-dried aorta were compared.MAIN OUTCOME MEASURES: ① Temperature curve of freeze-drying procedure. ②The reeze-drying procedure was scanned by micro-CT. ③ Changes of mechanical property were detected by TRAPEZIUM LITE texture analyzer and puncture experiments.RESULTS: During freeze-drying procedure, there were presented layer phenomenon in pig aorta. Compared to the fresh aorta, the freeze-dried aorta after recover water would reduce 40% axial tensile force, increase 45% circumferential tensile force, with 75% puncture stress.CONCLUSION: The freeze-dried blood vessel maintains mechanical property as fresh vessel, thus, freeze-drying can be used for vascular preservation.