Facile Microembossing Process for Microchannel Fabrication for Nanocellulose-Paper-Based Microfluidics.

Area of Science:

• Materials Science
• Microfluidics
• Analytical Chemistry

Background:

• Nanofibrillated cellulose paper (nanopaper) is a promising substrate for paper-based microfluidics due to its unique properties.
• Existing methods for patterning microchannels on nanopaper have limitations in resolution, contamination, and scale.

Purpose of the Study:

• To develop a facile and high-resolution method for patterning microchannels on nanopaper.
• To demonstrate the application of this new patterning technique in microfluidic devices and sensors.

Main Methods:

• Microembossing using plastic micro-molds to pattern nanopaper.
• Optimization of patterning parameters and creation of a guideline table.
• Fabrication of laminar mixers, droplet generators, and nanopaper-based analytical devices (NanoPADs).

Main Results:

• Achieved microchannel patterning down to 200 μm, a 4-fold improvement over existing methods.
• Developed NanoPADs for glucose and Rhodamine B (RhB) sensing with significantly improved limits of detection (2 mM for glucose, 19 fM for RhB).
• Demonstrated time-saving patterning process (<45 mins).

Conclusions:

• The developed microembossing technique offers a significant advancement in nanopaper microchannel fabrication.
• The improved NanoPADs demonstrate the potential of this technique for highly sensitive and integrated analytical devices.
• This method facilitates the development of advanced paper-based microfluidic applications.