Abstract

How to process and preserve these biological material has always been a concerning problem. Vascular studying and evaluating the feasibility of preparing the vessel scaffold by freeze-drying technology is expected to provide high-qualified and reliable vascular graft for the clinical treatment of the related diseases. Judgment of the end of primary drying has always been a key point on the process of freeze-dried pig aorta, because it can directly affect the final quality of the dried sample if improper judgment has been used. In this study, different methods have been adopted to determine the endpoint of primary drying and then various methods of observation on the status of the aorta are used for contrast, including Micro-CT scanning, percentage of dehydration and calculation of the rehydrated rate and so on. From the results, differences are obvious. These experiments point out how to judge the endpoint of the pig aorta’s primary drying when they are freeze-dried by small laboratory equipments in which heat leakage and other external factors cannot be ignored.

Keywords:

End point of primary drying, freeze-drying, micro-CT scanning,

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