A New Fabrication Method for Paper-Based Microfluidic Device Used in Bio-Assay

Paper-based microfluidic devices have a significant potential for low-cost diagnostics in the developing world. This study reported a simple fabrication method based on the digitallization of microfluidic technology for paper based microfluidic devices. Melted wax was jetted steadily with PZT actuated microfluidic pulse inertia driving system and pulled-forged glass micronozzle in the form of droplets. The wax melted into filter paper to form hydrophobic wall and different patterns for paper microfluidic devices were made. The influence of system parameters such as driving force, frequency, the fabrication process and the tip diameter of glass micronozzle on the wax line width was experimentally studied. 75 μm500 μm wax lines were achieved with the wax printing system. The paper microfluidic devices fabricated could lead the capillary action of black ink and the color change reaction of NaOH and phenolphthalein solution. Result showed that the wax printing system is simple structured and this method suggests a novel path to develop simple, inexpensive, and portable diagnostic assays.