Conventional lateral flow tests and paper-based assays offer many advantages, including low cost, portability, easy fabrication, and simple operation that involves loading of a liquid sample.A capillary force-activated flow of the liquid through a porous network of the paper also eliminates the need for active pumping system, and the test results can be interpreted with the naked eye.Nevertheless, conventional strip-type format is not adequate to carry out sequential delivery of multiple reagents, which is essential to perform multi-step reactions such as sandwich immunoassay and a number of colorimetric reactions for enhancing test results.Several approaches for sequential delivery of fluids in paper-based microfluidic devices have been demonstrated by performing controlled flow rate and timed fluid delivery.However, conventional approaches still need a complicated manufacturing processes of paper-fluidic devices.