Abstract:

Suitable scaffold material is one of the keys to the successful construction of small caliber tissue engineering blood vessels in vitro. Fibrin gel with natural protein composition is an ideal source of scaffold materials. In this study, fibrinogen was used as raw material and mixed with a certain proportion of thrombin and calcium chloride, and the gel material was obtained through technical steps such as temperature control. Then, the clotting time, water absorption, degradation time and mechanical properties were tested. The microstructure of the material was observed by scanning electron microscope. Secondly, the hydrogel tubular scaffold was made by using a specific tubular mold. By loading human fibroblasts in the scaffold, the effect of fibrin gel scaffold on the growth of human fibroblasts was studied and its cytocompatibility was judged. The results show that the overall appearance of the fibrin gel obtained by this method is milky white, smooth and uniform in thickness; the average gel forming time is (172.0±4.7) s; the water absorption rate is 34.50%±1.87%; the complete degradation time is 7 days and the Young's modulus is (2624±295) Pa; the overall structure of the gel has certain stability; the microstructure of the gel is presented as porous mesh fibers, and the fiber diameter is (0.41±0.03) μm with average pore size of reticular fiber of (47.87±9.60) μm². After embedding human fibroblasts, the cells are morphologically intact and evenly distributed in the gel, and the cells survived well. This study provides a reference for the further study of in vitro construction of small caliber tissue engineering vascular graft.

Key words: fibrin gel, human fibroblast, porous tubular scaffold, vascular graft