3D-Printed Scaffolds from Alginate/Methyl Cellulose/Trimethyl Chitosan/Silicate Glasses for Bone Tissue Engineering

Abstract

Alginate-based hydrogel inks are commonly used in printing due to their biocompatibility, biodegradation, and cell adhesion. In the present work, 3D printing of hydrogels comprising alginate/methyl cellulose (MC)/trimethyl chitosan (TMC) and silicate glasses was investigated. It was found that TMC increased the stability of the scaffolds after immersion in normal saline solution in comparison with alginate/MC 3D constructs. The stability also remained after the incorporation of pure silicate glasses or bioactive glasses. Immersion in simulated body fluid (SBF) resulted in the formation of hydroxyapatite in all samples. Scanning electron microscopy (SEM) analysis revealed a good cell adhesion of pre-osteoblasts on all scaffold compositions, cell viability assessment displayed a proliferation increase up to seven days in culture, and alkaline phosphatase (ALP) activity was similar in all scaffold compositions without significant differences. Total collagen secretion by the pre-osteoblasts after 7 days in culture was significantly higher in scaffolds containing silicate glasses, demonstrating their ability to promote extracellular matrix formation. In conclusion, 3D-printed porous scaffolds based on alginate/methyl cellulose/TMC are promising candidates for bone tissue engineering applications.