Laser-treated hydrophobic paper: an inexpensive microfluidic platform

Area of Science:

• Materials Science
• Analytical Chemistry
• Biotechnology

Background:

• Microfluidic platforms are crucial for chemical and biological analyses.
• Traditional microfluidic devices can be expensive and complex to fabricate.
• Paper-based platforms offer a low-cost alternative but require precise surface modification.

Purpose of the Study:

• To develop an inexpensive and accessible method for fabricating paper-based microfluidic platforms.
• To demonstrate selective surface modification of hydrophobic paper using laser treatment.
• To showcase the utility of these platforms for chemical and biological analyses.

Main Methods:

• Utilizing a CO(2) laser to selectively alter the surface properties (hydrophobic to hydrophilic) of various hydrophobic papers.
• Achieving patterned features with a minimum size of 62±1 µm.
• Depositing silica microparticles onto patterned areas to facilitate lateral diffusion.

Main Results:

• Demonstrated selective hydrophobic-to-hydrophilic surface conversion on paper substrates.
• Created microfluidic patterns with high resolution.
• Showcased the ability to trap aqueous reagents and self-assemble droplet arrays.
• Successfully performed a chemical reaction for hemoglobin detection using the platform.

Conclusions:

• Laser treatment provides an effective and inexpensive method for fabricating functional paper-based microfluidic devices.
• The porous, modified surface is suitable for localizing reagents and enabling complex analytical procedures.
• This technology holds potential for developing low-cost diagnostic tools.