Cellular Influence on Viscosity: Rheological Characterization of Collagen-Based Bioinks
Abstract/Description/Artist Statement
Collagen hydrogels are widely utilized in tissue engineering for their biocompatibility and cellular support. Bioinks are cellular hydrogels used in bioprinting—a fabrication technique for tissue-like structures. Because low-concentration hydrogels often lack the mechanical strength for load-bearing applications, such as cartilage repair, high-concentration collagen formulations incorporating neonatal bovine chondrocytes have been developed. Rheology provides information about the behavior and printability of bioinks. The combined effects of high collagen and high cell concentrations on hydrogel rheology remain underexplored under conditions specific to our bioprinting approach. To evaluate these effects, the relationship between viscosity and shear rate of hydrogels with varying combinations of collagen and cell concentrations was analyzed. Collagen was extracted from rat tail tendons, solubilized and reconstituted into a 25 mg/mL stock. Chondrocytes were isolated from neonatal bovine condyles via dissection, enzymatic digestion, and centrifugation. Hydrogels were prepared by neutralizing collagen with a working solution and mixing with chondrocyte suspensions. Rheology results indicate that cell incorporation affects hydrogel viscosity, with variations observed across different collagen-cell combinations compared to acellular controls. The hydrogels exhibited shear-thinning behavior, with viscosity changing in response to shear rate. This study will inform the design and optimization of bioinks and bioprinting for tissue engineering applications.
Cellular Influence on Viscosity: Rheological Characterization of Collagen-Based Bioinks
Collagen hydrogels are widely utilized in tissue engineering for their biocompatibility and cellular support. Bioinks are cellular hydrogels used in bioprinting—a fabrication technique for tissue-like structures. Because low-concentration hydrogels often lack the mechanical strength for load-bearing applications, such as cartilage repair, high-concentration collagen formulations incorporating neonatal bovine chondrocytes have been developed. Rheology provides information about the behavior and printability of bioinks. The combined effects of high collagen and high cell concentrations on hydrogel rheology remain underexplored under conditions specific to our bioprinting approach. To evaluate these effects, the relationship between viscosity and shear rate of hydrogels with varying combinations of collagen and cell concentrations was analyzed. Collagen was extracted from rat tail tendons, solubilized and reconstituted into a 25 mg/mL stock. Chondrocytes were isolated from neonatal bovine condyles via dissection, enzymatic digestion, and centrifugation. Hydrogels were prepared by neutralizing collagen with a working solution and mixing with chondrocyte suspensions. Rheology results indicate that cell incorporation affects hydrogel viscosity, with variations observed across different collagen-cell combinations compared to acellular controls. The hydrogels exhibited shear-thinning behavior, with viscosity changing in response to shear rate. This study will inform the design and optimization of bioinks and bioprinting for tissue engineering applications.