Characterization of fluid flow in paper-based microfluidic devices

Abstract

Paper-based microfluidic devices are being leveraged for application of diagnostic and detection technology in low-resource settings. In order to design a highly accurate device, a mathematical model is required to predict flow behaviour in the paper-based microfluidic devices. A series of experiments were conducted to observe the parameters that influence fluid flow behaviour in paper during imbibition. The parameters investigated included temperature, humidity, machine direction, length, and width. Experiment results showed that variations in fluid temperature and width of the paper device influenced wicking time, and a post-wetting flow was also observed. Two common modelling methods, the Washburn equation and Darcy’s law, were evaluated to determine the most appropriate method for predicting flow behaviour in paper. A mathematical model was developed along with an empirically determined expression for permeability.