Reactive polymer coatings: a first step toward surface engineering of microfluidic devices

Area of Science:

• Biomedical Engineering
• Materials Science
• Cell Biology

Background:

• Microfluidic devices are crucial for high-throughput biological assays.
• Surface functionalization is key to controlling molecular interactions within microchannels.
• Developing robust methods for immobilizing biomolecules is essential for reliable cell capture.

Purpose of the Study:

• To fabricate and characterize novel microfluidic devices for cell analysis.
• To functionalize polydimethylsiloxane (PDMS) microdevices with a reactive coating for biomolecule immobilization.
• To demonstrate the utility of these devices in cell-based bioassays.

Main Methods:

• Chemical vapor deposition (CVD) polymerization of poly[para-xylylene carboxylic acid pentafluorophenolester-co-para-xylylene] on PDMS microfluidic devices.
• Immobilization of amino-terminated biotin ligands onto the functionalized surface.
• Characterization of the coating's adhesion and uniformity using fluorescence microscopy.
• Cell-based bioassay using the disintegrin echistatin to monitor concentration-dependent cell adhesion.

Main Results:

• Successful functionalization of PDMS microfluidic devices with a uniform, adhesive coating (~100 nm).
• Demonstrated effective self-assembly of proteins, antibodies, and mammalian cells on the functionalized surface.
• Quantified the concentration-dependent effect of echistatin on cell adhesion, validating the device's performance.

Conclusions:

• The developed microfluidic devices provide a robust platform for surface-immobilized cell capture.
• The functionalization method ensures uniform distribution of ligands, enabling sensitive cell-based assays.
• This technology holds potential for applications in clinical research, particularly in angiogenesis studies.