Air-stable supported membranes for single-cell cytometry on PDMS microchips

Area of Science:

• Biomaterials Science
• Analytical Chemistry
• Microfluidics

Background:

• Supported bilayer membranes (SBMs) are crucial for microfluidic devices but often lack long-term stability.
• Developing robust coatings for microchip electrophoresis is essential for reliable and reproducible separations.

Purpose of the Study:

• To develop and evaluate protein-reinforced supported bilayer membranes (rSBMs) for enhanced stability and performance in microchip electrophoresis.
• To assess the durability of rSBM coatings under various conditions, including dehydration and cellular biofouling.

Main Methods:

• Novel plasma oxidation method developed for rapid hydrophilic substrate preparation.
• Assembly of rSBMs (phosphatidylcholine, biotin-PE, Neutravidin) on hybrid polydimethylsiloxane (PDMS) and glass microchips.
• Evaluation of electroosmotic mobility and separation efficiencies for fluorescent dyes and peptides using microchip electrophoresis.

Main Results:

• rSBM-coated channels demonstrated high separation efficiencies (up to 700,000 plates m(-1)).
• rSBM coatings showed significantly improved stability against dehydration and rehydration cycles compared to standard PC coatings.
• rSBM-coated devices maintained performance after prolonged dehydrated storage and were effective in single-cell cytometry.

Conclusions:

• rSBMs provide a rugged and stable coating solution for microfluidic devices, overcoming limitations of traditional SBMs.
• The developed rSBM technology enables reliable microchip electrophoresis applications, including those involving single-cell analysis.
• These findings pave the way for more durable and versatile microfluidic platforms in analytical sciences.