Optimising Bioprinting Nozzles through Computational Modelling and Design of Experiments.

Area of Science:

• Biotechnology
• Tissue Engineering
• Biomedical Engineering

Background:

• 3D bioprinting offers potential for creating artificial tissues and organs.
• Cell damage during bioprinting, particularly extrusion methods, leads to low cell viability (40-80%).
• Nozzle geometry is a critical factor influencing cell viability in 3D bioprinting.

Purpose of the Study:

• To review studies utilizing computational fluid dynamics (CFD) for optimizing 3D bioprinting nozzle geometry.
• To identify optimal nozzle design parameters and operating conditions to improve cell viability.
• To present a design of experiments (DOE) approach for optimizing bioink printing configurations.

Main Methods:

• Review of existing research employing computational fluid dynamics (CFD) to analyze fluid flow and shear stress within bioprinter nozzles.
• Analysis of experimental data to determine optimal nozzle dimensions (diameter, length, angle) and surface treatments.
• Application of Design of Experiments (DOE) to identify optimal bioprinting parameters for bioinks.

Main Results:

• Optimal nozzle diameter: 0.2 mm to 1 mm; Optimal nozzle length: 8 mm to 10 mm.
• Recommended internal nozzle angle: 20 to 30 degrees.
• Recommended internal coating: ethylenediaminetetraacetic acid (EDTA); Target shear stress: < 10 kPa.

Conclusions:

• CFD is an effective tool for optimizing 3D bioprinting nozzle design to reduce cell damage.
• Specific nozzle geometries and operating conditions can significantly improve cell viability in bioprinted constructs.
• DOE methodologies can further refine bioprinting processes for enhanced tissue engineering outcomes.