Submicron Patterns-on-a-Chip: Fabrication of a Microfluidic Device Incorporating 3D Printed Surface Ornaments.

Area of Science:

• Biomaterials Engineering
• Tissue Engineering
• Microfluidics

Background:

• Studying bone regeneration requires in vitro models that replicate the complex, multiscale architecture of bone tissue.
• Existing methods face challenges in creating high-fidelity, large-area submicron topographies for 3D cell cultures.

Purpose of the Study:

• To engineer a microfluidic platform with reproducible, large-area submicron pillar topographies for advanced bone regeneration research.
• To demonstrate the capability of two-photon polymerization for fabricating multiscale structures within a microfluidic device.

Main Methods:

• Utilized two-photon polymerization (2PP) with optimized parameters and direct laser writing to create uniform submicron pillar patterns.
• Integrated submicron pillars of varying heights onto 3D microscaffolds in a single fabrication step.
• Assessed surface hydrophilicity, mechanical stability under flow, and cytotoxicity of the fabricated materials.

Main Results:

• Successfully fabricated a microfluidic platform with mm-scale, reproducible submicron pillar topographies.
• Demonstrated multiscale fabrication by integrating pillars of different heights onto 3D microscaffolds.
• Observed improved surface hydrophilicity and stability at flow rates up to 8 mL/min.
• Confirmed no cytotoxic effects of the IP-Dip resin on human mesenchymal stromal cells in dynamic culture.

Conclusions:

• This study presents a significant advancement in creating submicron structure-on-a-chip models for bone regeneration.
• The developed microfluidic platform offers a promising tool for high-throughput in vitro studies of bone tissue engineering.
• The fabrication method allows for precise control over microscale features essential for mimicking the native tissue microenvironment.