The correlation between rheological properties and extrusion-based printability in bioink artifact quantification

Area of Science:

• Biomaterials Science
• Biotechnology
• Materials Engineering

Background:

• Limited availability and inconsistent performance of bioinks hinder cell-based bioprinting.
• Comprehensive printability assessment and understanding rheological influences are crucial for bioink development.

Purpose of the Study:

• To investigate the relationship between rheological properties and printing outcomes in bioinks.
• To develop and utilize a specialized bioink artifact for improved printability quantification.
• To assess shape fidelity across various hydrogel-based bioinks.

Main Methods:

• Developed a specialized bioink artifact for extrusion-based bioprinting.
• Selected seven hydrogel-based bioinks for testing.
• Conducted rheological measurements and assessed printing outcomes using the artifact.
• Analyzed correlations between rheological metrics and printing performance.

Main Results:

• High-performing bioinks demonstrated high storage modulus, low tan(delta), shear-thinning, high yield stress, and rapid recovery.
• Storage modulus and tan(delta) showed strong correlation (R² > 0.9) with gap-spanning and turn accuracy.
• Bioink artifact facilitated quantification of printability across diverse bioinks.

Conclusions:

• Rheological properties significantly influence bioink printing outcomes, though not fully predictive alone.
• A holistic assessment combining rheology and direct printability measurement is essential.
• Standardized methods and enhanced bioink availability are needed for advancing bioprinting.