Actuation and Flow Control in Paper-Based Microfluidics by Varying Thickness of Storage Reservoir

This paper discusses the potential of paper-based microfluidic devices for affordable diagnostics, and the importance of flow control. We have explored the variation of the width of paper, effect of 2D flow, and altering the surface wettability of paper to increase the resistance to fluid flow by physicochemical barriers. We used Whatman filter paper No. 40 and No. 1, mustard oil, and oleic acid, to examine the fluid flow due to capillary forces. Moreover, the effect of increase in thickness of the storage reservoir to decrease flow rate in the paper was also investigated. The experiments provide valuable insights into the behavior of fluid flow in porous media, and the findings have important applications in biomedical diagnostics and environmental monitoring.