Engineering enhanced flow control in paper

G.IJ. Salentijn, N.N. Hamidon, Y. Hong, E. Verpoorte
University of Groningen,

Keywords: paper microfluidics, selective permeability, on/off valving


The hallmark of microfluidics is the unique ability to controllably manipulate minute liquid volumes to achieve enhanced and accelerated (bio)chemical processing. As a relative newcomer to the field, paper microfluidics provides a promising alternative to existing glass and polymer microchannel chips for the fabrication of low-cost, easy-to-use devices. In particular, the innate ability of the porous paper matrix to passively transport liquids by capillary action could dramatically simplify device use by eliminating the need for active pumping and valving. The control of passive flows in hydrophobically patterned paper channels, however, brings with it new demands with respect to device design. In particular, it is still desirable to be able to temporally and spatially dictate solution flows, implying the implementation of additional passive flow control components. In this work, we introduce an approach we term selective permeability to achieve solvent-dependent on/off valving in paper microfluidic devices for the realization of more complex reactions and processes.