مرتضي كوهي كرگان

Additive manufacturing (AM) or 3D printing has caused a revolution in the production world due to its distinctive features compared to other manufacturing processes. Today, the most important application of 3D printers is in tissue engineering and the construction of biological scaffolds. Accordingly, tissue engineering in order to rebuild and treat tissue, missing textures, offers new methods. An ideal scaffold should have biocompatible conditions in the body environment and also suitable strength for replacement at the site of the damaged tissue. The purpose of this research was to use the extrusion manufacturing method (Robocasting) to print biological scaffolds with hydroxyapatite powder and increase the mechanical and biological properties by infiltrating gelatin and achieving an infiltrating phase composite (ICP). In order to investigate the factors affecting the printing of scaffolds, various extruders have been used, and the pneumatic extruder system has the best performance. Also, for printing scaffolds, parameters such as printing speed, structure's geometry, nozzle diameter and material outflow rate have been studied and wind pressure of 0.75 bar and print speed of 5 mm/s were part of the optimal results, Co-precipitation method has also been used to prepare hydroxyapatite powder. The operation of calcining the synthesized powder at 1000 temperatures and sintering of printed scaffolds at 1350 temperatures has taken place. Various powders and additives have been used to prepare a suitable paste for printing, which is synthesized powder and hydroxypropyl methyl cellulose has the best performance as an additive. Also, for polymer phase penetration and formation of diffusion phase composite, ICP of gelatinous solution with different weight percentages, and for eva‎luation of mechanical properties, pressure testing has been used. Also, in order to increase mechanical properties, gelatin penetration has been used from different percentages of weight. In the following, XRD, EDS and MAP analyzes were used to examine the synthesized powder, the flow test was used to examine the behavior of the paste, and the SBF test was used to examine the biological properties of the scaffolds.

ساخت افزايشي , مهندسي بافت , هيدروكسي آپاتيت , خواص مكانيكي , ژلاتين

Additive manufacturing , tissue engineering , hydroxyapatite , mechanical properties , gelatin

Morteza Koohi

Dr. Hossein Sarpoolaky- Dr. ‪Seyed Amir Ghaffari‬‬‬‬‬‬‬‬‬‬‬‬