Laser Direct Writing of Dual-Scale 3D Structures for Cell Repelling at High Cellular Density

Area of Science:

• Biomaterials Engineering
• Surface Science
• Nanotechnology

Background:

• Developing cell-repellent surfaces is crucial for advanced medical devices.
• Topographical features, like dual-scale structures, can control cell-material interactions.
• Laser-based fabrication offers potential but often lacks precise control over topography.

Purpose of the Study:

• To report the laser fabrication of reproducible, dual-scale 3D structures with high spatial accuracy.
• To design and optimize these structures for effective cell repellency.
• To investigate the influence of laser parameters on structure formation and cell interaction.

Main Methods:

• Laser Direct Writing via Two-Photon Polymerization of IP-Dip photoresist.
• Design of micrometric "mushrooms" with nanometric fingerprint-like features.
• Optimization of laser writing parameters, particularly laser power.

Main Results:

• Achieved fully reproducible and accurate dual-scale 3D structures.
• Demonstrated significant cell-repellent properties, effective even at high cellular densities.
• Identified optimal periodicity and height of nanofeatures (around 200 nm) for maximum repellency.
• Laser power emerged as the most critical parameter for optimization.

Conclusions:

• Laser Direct Writing enables precise fabrication of complex, cell-repellent surfaces.
• Dual-scale topographical features mimicking natural repellent surfaces are highly effective.
• Optimized nanostructured interfaces hold promise for next-generation medical devices with reduced biofouling.