Direct Micromachining of Microfluidic Channels on Biodegradable Materials Using Laser Ablation

Area of Science:

• Materials Science and Engineering
• Biomedical Engineering
• Microfluidics

Background:

• Laser patterning offers a flexible, rapid, and green manufacturing approach for polymers, ideal for prototyping.
• Microfluidic systems mimic natural vasculature, requiring precise fabrication techniques.
• Traditional microfabrication methods like MEMS lack the flexibility needed for certain applications.

Purpose of the Study:

• To develop a polymer surface modification method using a 193 nm excimer laser for microfluidic system fabrication.
• To investigate laser ablation on poly(dimethyl siloxane) (PDMS), poly(glycerol sebacate) (PGS), and poly(1,3-diamino-2-hydroxypropane-co-polyol sebacate) (APS).
• To analyze fabrication parameters and hydrodynamic properties of laser-patterned microchannels.

Main Methods:

• Utilized a 193 nm excimer laser system for direct laser machining of polymeric materials.
• Investigated laser ablation parameters including beam size, defocus distance, firing frequency, and ablation speed.
• Performed hydrodynamic simulations to compare laser-patterned channels with natural blood vessels.

Main Results:

• PGS and APS surfaces exhibited superior laser ablation quality, with precise channel widths and minimal surface fractures compared to PDMS.
• A linear relationship was observed between laser beam size, channel depth, and ablation efficiency.
• Ablation efficiency and edge quality on PGS and APS were higher than on PDMS, indicating suitability for direct laser machining.

Conclusions:

• Biodegradable polymers PGS and APS are highly applicable for direct laser machining of microfluidic systems.
• Laser-patterned U-shaped channels demonstrate hydrodynamic similarities to natural blood vessels.
• The developed laser patterning method is suitable for microfabrication and biomedical engineering applications.