One-step patterning of hollow microstructures in paper by laser cutting to create microfluidic analytical devices

TLDR

The paper presents a simple, low‑cost method for rapid, reproducible fabrication of paper‑based microfluidics using a commercial CO₂ laser cutter. The method uses a single laser‑cut operation to pattern hollow microstructures that act as hydrophobic barriers, with laser current and cutting rate optimized to achieve high resolution and multiplexed analytical capability. A 4 cm × 4 cm device can be produced in 7–20 s and is ready for use immediately, demonstrating high resolution and multiplexed analytical performance.

Abstract

In this paper, we report a simple, low-cost method for rapid, highly reproductive fabrication of paper-based microfluidics by using a commercially available, minitype CO(2) laser cutting/engraving machine. This method involves only one operation of cutting a piece of paper by laser according to a predesigned pattern. The hollow microstructures formed in the paper are used as the 'hydrophobic barriers' to define the hydrophilic flowing paths. A typical paper device on a 4 cm × 4 cm piece of paper can be fabricated within ∼7-20 s; it is ready for use once the cutting process is finished. The main fabrication parameters such as the applied current and cutting rate of the laser were optimized. The fabrication resolution and multiplexed analytical capability of the hollow microstructure-patterned paper were also characterized.