The motivation of this work is to present a new concept
of creating microfluidic patterns and channels by generating a
hydrophilic–hydrophobic contrast on the paper surface, forming
liquid penetration channels, rather than building patterns using
a physical polymer barrier. Building barriers in paper to define
channels is a limiting process to the speed and cost of large scale
fabrication, as it usually involves multiple steps including poly-
mer impregnation and pattern development. The ink jet printing
approach reported in this study can fabricate paper-based microflu-
idic patterns in a single printing step