System And Processing Of Layer-by-layer Imprinting Of 3D Soft Tissue Scaffolds

The tissue engineering includes three elements which are cells, growth conditions and scaffold. The scaffold provides a template and support for the growth of the tissue,and it plays a central role for the reconstruction of the tissue. It requires the soft tissue scaffold has three-dimensional microfluidic system when we build the soft tissue,for its large volume and complex network of blood vessels and so on.However, this structure can’t be produced in the traditional method of porous scaffolds. In recent years,due to the development of rapid prototyping technology, It becomes easy to manufacture complex structure scaffold and can be used for micro negative type technology to make single-layer scaffolds, as the same,by manual assembly become three-dimensional scaffold but this approach mainly applied to synthetic materials. Such as silk fibroin,collagen, cellulose, chitosan and gelatin and other natural biomaterials, all these material are similar to the extracellular matrix characteristics,so its production efficiency and machining accuracy is poor. To solve these problems, we research the imprint-forming system and process optimization of three-dimensional microfluidic scaffold and evaluate the physical and biological properties of the scaffold.This paper build a three-dimensional layer-by-layer imprinting machine hardware and software system. The hardware system mainly includes three dimensional motion platform, freezing module, injection module, heating module and mold.The software system is built with Qt library and C+ + language.Research the optimization of 3D imprint processor parameters.Acquire the mechanical properties and the swelling of gelatin material by swelling test and pressure test. Design of the internal three-dimensional scaffold with groove structure model in Solid Works software. Produced the silicone mold;Through calibration experiments of injection pump improved the precision of injection pump injection;Based on the research of the scaffold post-processing experiment, optimized the gelatin with enzyme crosslinking temperature and the time;By using Ansys software to support internal flow channel are analyzed in fluid mechanics.Evaluation is given to the groove structure of three-dimensional gelatin, port connectivity and biological properties.Measure the groove structure of the manufacturingprecision of the groove size evaluation;By perfusion experiment, evaluate the bracket of the internal flow guide connectivity;Biological evaluation before the post-treatment process of scaffolds; vascular endothelial cells were seeded on our three-dimensional scaffold flow passage statically in 3 days to evaluate the biological performance.This study shows that the 3D imprinting machine is able to make three-dimension groove structure soft tissue scaffolds with gelatin production, and improve the bracket forming efficiency and forming precision, and shows that gelatin scaffold has good biological properties.