Dung Quoc NGUYEN, Nghia Thi Hieu PHAN, Ha Le Bao TRAN
Vol. 13 (2024) p. 293-300

The utilization of calcium chloride (CaCl2) pre-crosslinking in gelatin-alginate ink holds promise for creating printable ink formulations that exhibit good printability and do not compromise the viability of cells. This study focuses on the development of ink formulations using CaCl2 pre-crosslinking, ensuring both printability and safety against cytotoxicity. In this study, the gelatin-alginate hydrogel was combined with varying concentrations of CaCl2 (60 mM, 70 mM, and 80 mM) to create four ink formulations. Then, the printability of these inks was assessed, and the best formulation was selected for printing the desired structure. Subsequently, cytotoxicity and cell viability of the printed structure were evaluated. The results suggested that among these formulations, the ink containing gelatin: alginate: 70 mM CaCl2 in a 1 : 1 : 0.5 volumetric ratio exhibited good printability characterized by smooth and straight ink filaments, with a printability (Pr) value of 0.93 ± 0.044. Importantly, cytotoxicity assessments demonstrated that this ink was non-toxic to L929 cells, with a relative growth rate of 83.29%. Furthermore, viability studies using human fibroblast cells showed sustained cell viability within the scaffold structure for at least 24 hours under standard culture conditions. These results highlight the potential of using the gelatin-alginate ink formulation in extrusion-based three-dimensional (3D) printing methods for constructing scaffolds in tissue engineering applications.