3D Printing Type 1 Bovine Collagen Scaffolds for Tissue Engineering Applications—Physicochemical Characterization and In Vitro Evaluation

• Published in: Gels 2023-08, Vol.9 (8), p.637
• Main Authors: Nayak, Vasudev Vivekanand, Tovar, Nick, Khan, Doha, Pereira, Angel Cabrera, Mijares, Dindo Q, Weck, Marcus, Durand, Alejandro, Smay, James E, Torroni, Andrea, Coelho, Paulo G, Witek, Lukasz
• Format: Article
• Language: English
• Subjects: 3-D printers; 3D printing; additive manufacturing; Alkaline phosphatase; Biocompatibility; Biomedical materials; bovine collagen; Calorimetry; Cattle; Collagen; Crosslinked polymers; Crosslinking; Cytotoxicity; Denaturation; Fourier transforms; Gels; Infrared analysis; Infrared spectroscopy; Inkjet printing; lyophilizing; Phosphatases; Polymers; Proteins; Raw materials; Rheological properties; Scaffolds; Scientific equipment and supplies industry; Shear stress; Shear thinning (liquids); Thermal stability; Thermogravimetric analysis; Three dimensional printing; Tissue engineering; Viscoelasticity; Viscosity; Yield stress
• ISSN: 2310-2861; 2310-2861
• DOI: 10.3390/gels9080637

Collagen, an abundant extracellular matrix protein, has shown hemostatic, chemotactic, and cell adhesive characteristics, making it an attractive choice for the fabrication of tissue engineering scaffolds. The aim of this study was to synthesize a fibrillar colloidal gel from Type 1 bovine collagen, as well as three dimensionally (3D) print scaffolds with engineered pore architectures. 3D-printed scaffolds were also subjected to post-processing through chemical crosslinking (in N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide) and lyophilization. The scaffolds were physicochemically characterized through Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis, Differential Scanning Calorimetry, and mechanical (tensile) testing. In vitro experiments using Presto Blue and Alkaline Phosphatase assays were conducted to assess cellular viability and the scaffolds’ ability to promote cellular proliferation and differentiation. Rheological analysis indicated shear thinning capabilities in the collagen gels. Crosslinked and lyophilized 3D-printed scaffolds were thermally stable at 37 °C and did not show signs of denaturation, although crosslinking resulted in poor mechanical strength. PB and ALP assays showed no signs of cytotoxicity as a result of crosslinking. Fibrillar collagen was successfully formulated into a colloidal gel for extrusion through a direct inkjet writing printer. 3D-printed scaffolds promoted cellular attachment and proliferation, making them a promising material for customized, patient-specific tissue regenerative applications.