High-Precision Paper-Based Microfluidic Devices Fabrication Based on Laser Cutting Method

To explore a simple, fast and high-precision paper-based devices fabrication method, a paper-based microfluidic devices fabrication method based on CO2 laser cutting technology is proposed in this paper, in which the filter paper is fixed with aluminum foil, and the hydrophobic barrier is formed by laser cutting the adhered filter paper. High-precision paper-based devices can be produced quickly and in large quantities due to the adjustable laser power magnitude and movement speed. The minimum hydrophilic channel width of the paper-based devices made by this method is
$76\pm 2\ \mu\mathrm{m}$
and the minimum hydrophobic barrier width is
$90\pm 3\ \mu\mathrm{m}$
, which greatly reduces the size of the paper-based devices. The paper-based devices made by this method for the detection of nitrite concentration obtained good linearity and good agreement with the spectrophotometry for the detection of nitrite. The paper-based devices made by laser cutting method are simple, low manufacturing cost, stable process method and good consistency for mass production, which provides an effective means for the research and wide application of paper-based devices.