Formulation of chitosan and chitosan-nanoHAp bioinks and investigation of printability with optimized bioprinting parameters

• Published in: International journal of biological macromolecules Vol. 222; pp. 1453 - 1464
• Main Authors: Coşkun, Sema, Akbulut, Serdar Onat, Sarıkaya, Burcu, Çakmak, Soner, Gümüşderelioğlu, Menemşe
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2022
• Subjects: 3D bioprinting; Amorphous nanohydroxyapatite; Bioink; Chitosan; Response surface methodology; 3D bioprinting; Chitosan; Response surface methodology; Bioink; Amorphous nanohydroxyapatite
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2022.09.078

The development of a chitosan-based bioink that can provide a cell-friendly environment at relatively low concentration and moderate cross-linking conditions is still problematic. Here, we developed amorphous nanohydroxyapatite (nHAp) containing chitosan bioink formulations that can be gelled via the inclusion of glycerol phosphate (GP) and sodium hydrogen carbonate (SHC) into the polymer network under physiological conditions. Rheological analyses indicated that all the formulations showed shear-thinning characteristics compatible with the extrusion-based bioprinting. Also, the chitosan bioinks exhibited more gel-like structure as the weight fraction of nHAp increased from 10 % to 40 %. The printability of the chitosan-based bioinks was assessed and optimized by response surface methodology (RSM). These studies revealed that all the formulations can be successfully printed within the ranges of 50–70 kPa printing pressure and 4–11 mm/s printing speed. Multi-layered chitosan biomaterials with distinct pore structure were successfully fabricated with a high printability index. High cell viability was observed after bioprinting with pre-osteoblastic MC3T3-E1 cells. In conclusion, this study represents for the first time that chitosan biomaterials bearing suitable rheological properties and cellularity can be printed with controllable architecture for 3D bone scaffolds. [Display omitted] •Low concentration (<3 w%) chitosan bioinks were developed.•Rheological and mechanical properties of chitosan bioink were significantly improved with the addition of nHAp.•RSM studies revealed optimum pressure (50–70 kPa) and speed (4–11 mm/s) ranges for reproducible bioprinting.•Chitosan-nHAp bioinks containing cells were directly printed under mild conditions without using a coagulation bath.•High cell viability was observed in the printed structure with distinct pore structure and high printability index.