Fluidic devices with diaphragm valves

A microfluidic device comprising a fluidics layer and an elastic layer contacting a face of the fluidics layer, wherein:

• (a) the fluidics layer comprises a plurality of fluid conduits comprising fluid-contacting surfaces, wherein at least a portion of the fluid-contacting surfaces are exposed to the elastic layer;
• and
• (b) the face comprises sealing surfaces bonded to the elastic layer to seal the fluid conduits at exposed fluid-contacting surfaces;
• wherein at least a portion of the exposed fluid-contacting surfaces comprise a low surface energy material having greater hydrophobicity than a sealing surface.

A system comprising:

• (a) a microfluidic device comprising a fluidics layer, an actuation layer and an elastic layer sandwiched between them, wherein:
• (i) the fluidics layer and the actuation layer comprise sealing surfaces that contact the elastic layer;
• and
• (ii) the fluidics layer comprises a plurality of fluid conduits comprising surfaces, and the actuation layer comprises a plurality of actuation conduits comprising surfaces, wherein at least a portion of the surfaces of the fluid conduits and actuation conduits are exposed to the elastic layer and wherein at least a portion of the exposed surfaces comprise a low surface energy material, and further comprising a plurality of diaphragm valves that each regulate fluid flow in a fluid conduit, wherein each diaphragm valve comprises:
• (1) a body comprising an exposed surface of the actuation layer, (2) a valve seat comprising an exposed surface of the fluidic layer, (3) a diaphragm comprised in the elastic layer and configured to sit on or off a surface of the valve seat, and (4) valve ports configured to allow fluid to enter and exit the valve, wherein at least a portion of the valve seat surface comprises the low surface energy material;
• (b) a fluid delivery system configured to deliver fluid to the fluidic conduits;
• and
• (c) a control system configured to control the actuation layer.

A method comprising:

• (a) creating a sandwich comprising a first layer comprising at least one conduit exposed to a surface, a second layer comprising at least one conduit exposed to a surface, and an elastic layer between the two surfaces;
• (b) bonding the elastic layer to the surfaces;
• and
• (c) flushing the conduits with PEG or 1-2 propane diol.

A microfluidic device comprising a fluidics layer, an actuation layer and an elastic layer sandwiched between them, wherein:

• (a) the fluidics layer and the actuation layer comprise sealing surfaces that contact the elastic layer;
• and
• (b) the fluidics layer comprises a plurality of fluid conduits comprising surfaces, and the actuation layer comprises a plurality of actuation conduits comprising surfaces, wherein at least a portion of the surfaces of the fluid conduits and actuation conduits are exposed to the elastic layer;
• wherein the microfluidic device comprises a plurality of diaphragm valves that each regulate fluid flow in a fluid conduit, wherein each diaphragm valve comprises (i) a body comprising an exposed surface of the actuation layer and in the fluidics layer, (ii) a diaphragm comprised in the elastic layer and configured to sit on or off a surface of the valve seat, and (iii) valve ports configured to allow fluid to enter and exit the valve, wherein at least a portion of the exposed surface of the fludics layer in the body is derivatized with a binding functionality.