Self-regenerating and hybrid irreversible/reversible PDMS microfluidic devices

Area of Science:

• Materials Science
• Microfluidics Engineering

Background:

• Fabricating microfluidic devices, particularly those using polydimethylsiloxane (PDMS), often involves complex and costly procedures.
• Existing methods may require specialized equipment like plasma etchers or UV ozone cleaners, limiting accessibility and increasing fabrication time and expense.

Purpose of the Study:

• To introduce a simple, rapid, and low-cost method for fabricating high-performance PDMS microfluidic chips.
• To demonstrate a bonding technique that avoids surface oxidation and chemical modifications, allowing for greater flexibility in device design and prototyping.

Main Methods:

• The study details a novel fabrication technique termed sandwich bonding (SWB).
• SWB involves reversible bonding of a coverslip to PDMS channels, followed by pouring liquid PDMS monomers and a curing agent, and subsequent curing in a laboratory oven.
• The method was successfully applied to bond PDMS to glass, gold (Au), and aluminum (Al).

Main Results:

• SWB produces high-performance microfluidic channels with hybrid irreversible/reversible bonding characteristics.
• The fabricated chips exhibit self-regeneration capabilities after leakage events.
• The reversible bonding allows for easy detachment of components (PDMS substrate and glass coverslip) for reuse, reducing waste and cost.

Conclusions:

• Sandwich bonding (SWB) offers a straightforward, fast, and economical alternative for PDMS microfluidic chip fabrication.
• The technique's ability to create reusable, self-regenerating, and versatile chips makes it highly valuable for research and development in microfluidics.
• SWB facilitates prototyping of hybrid devices and allows for surface modifications prior to bonding, overcoming limitations of traditional methods.