Model Design and Path Optimization of Perfusable Chips in Extrusion-Based Bioprinting: Linking Hydrogel Rheology with...

Area of Science:

• Biotechnology
• Materials Science
• Biomedical Engineering

Background:

• Extrusion-based bioprinting offers precise control, cost-effectiveness, and versatility.
• Limited research exists on the interplay between material properties, structural design, and process optimization in bioprinting.

Purpose of the Study:

• To investigate the relationships among hydrogel rheology, model structural characteristics, and path planning strategies.
• To optimize bioprinting processes for fabricating complex 3D constructs, including unsupported overhangs and perfusable chips.

Main Methods:

• Evaluated printability of low- and high-viscosity hydrogels using pattern arrays and 3D grid constructs.
• Designed and printed a perfusable chip with various features (flat, support, wall, overhangs).
• Optimized printing path based on hydrogel rheological properties to overcome limitations in fabricating unsupported overhangs.

Main Results:

• Low-viscosity hydrogels are suitable for patterns with frequent extrusion changes; high-viscosity hydrogels are better for scaffolds.
• Successfully fabricated a 10 × 10 mm² overhanging structure and perfusable hydrogel chips.
• The fabricated chips demonstrated reliable flow performance and sealing capacity, with a maximum burst pressure of 1.2 kPa.

Conclusions:

• A design framework integrating material properties, structural features, and path planning was developed.
• This framework optimizes extrusion-based bioprinting processes for advanced 3D cell culture systems.
• The study provides valuable insights for constructing complex bioprinted architectures.