Figure 2.

Amplification buffer delivery using the novel paper network geometry involving two dissimilar porous materials and pinch valve. The membrane overlap between the first and second fluidic paths enables delivery of each set of fluids orthogonally. The device uses water-soluble (WS) paper surrounding a lever arm that holds a pinch valve close (A). The first three steps; sample, conjugate, and wash steps, are delivered across the primary fluidic path (B). As the wicking pad wets, the water-soluble paper that is placed in contact with it wets until the force of the lever arm overcomes the strength of the paper. This leads to the release of the lever arm and opening the pinch valve (C). Now open, the amplification buffer is delivered via the secondary fluidic path and onto the nitrocellulose test membrane (D).