Phaseguide technology gives complete control over filling and emptying of any type of microfluidic structures, independent of the chamber and channel geometry. The technique is based on a step-wise advancement of the liquid-air interface using the meniscus pinning effect. In this paper, the main effects and parameters underlying the phaseguiding principle are discussed and a demonstration is given of its potential for dead angle filling, spatially controlled phaseguide overflow and sequential phaseguide overflow, all accumulating in a passive valving approach. Phaseguides represent a new direction in microfluidic design thinking that will prove a leap forward towards more simple, flexible and reliable microfluidic systems.
© The Royal Society of Chemistry 2011