Channel-less pump, methods, and applications thereof
A channel-less microfluidic pump includes a cartridge including a substrate and an actuatable film layer disposed on the substrate, and a manifold having at least three actuatable void volumes separated by a plurality of wall sections and an actuatable flexible layer disposed on the manifold interfacing the actuatable film layer. In operation, the pump can be in an unactuated state wherein the actuatable film layer is disposed against the surface of the substrate or an actuated state wherein at least a portion of the flexible layer and a corresponding portion of the actuatable film layer are deflected into a corresponding void volume thus forming a fluidic volume between the deflected portion of the actuatable film layer and the surface of the substrate. In the actuated state, there is a fluidic gap between immediately adjacent void volumes formed by a thinned region of the flexible layer at a point of contact with a top surface of a wall section. A method of transporting fluid using the channel-less microfluidic pump is described.
1. A method for making a microfluidic cartridge, comprising:
providing a substrate having opposing, flat external surfaces and a via extending there between, and an actuatable film layer disposable on a one of the opposing, flat external surfaces, wherein there are no dedicated structural fluidic microchannels disposed between the substrate and the actuatable film;
providing a fixture having opposing external surfaces wherein one of the external surfaces has at least one hollow formed therein and a corresponding vacuum channel extending from the other external surface and intersecting the corresponding hollow;
disposing a blister material on the external surface of the fixture containing the hollow;
applying a negative pressure through the vacuum channel and drawing the blister material against the external surface of the fixture and into the at least one hollow;
delivering a fluid into the blister material-lined hollow;
disposing the substrate onto the blister material covering the external surface of the fixture containing the hollow such that the via intersects the blister material-lined hollow;
applying the actuatable film layer to the exposed substrate surface thus sealing the via and the blister material-lined hollow;
removing the cartridge consisting of the actuatable film layer, the substrate, and the fluid-filled blister material from the fixture; and
providing a protective cover applied to at least a portion of the surface of the blister material opposite the side of the blister material to which the substrate is engaged.
2. The method of claim 1 , wherein the substrate has a thickness equal to or less than one millimeter (1 mm).
3. The method of claim 1 , wherein the substrate is permanently adhered to the blister material through at least one of ultrasonic bonding, RF bonding, laser welding, thermal bonding, adhesive lamination, and solvent bonding.
4. The method of claim 1 , wherein the actuatable film layer is selectively bonded to regions of the substrate so that the actuatable film layer can modulate an opening and closing of the via.
5. The method of claim 1 , wherein the actuatable film layer has a hydrophobic coating.
6. The method of claim 5 , wherein the hydrophobic coating is wax.
7. The method of claim 1 , wherein the protective cover is vented.
8. The method of claim 1 , wherein the protective cover forms at least one chamber reservoir enclosing the fluid-filled blister.
9. The method of claim 8 , wherein the protective cover forms at least one chamber that is accessible through a via in the blister material.
10. The method of claim 9 , wherein the via in the blister material is aligned with a corresponding substrate via.
11. The method of claim 8 , wherein the at least one chamber reservoir is a sample reservoir having a sample input port.
12. The method of claim 11 , wherein the at least one chamber reservoir is a reagent storage reservoir.
13. The method of claim 12 , wherein the at least one reagent storage reservoir is provided with a plurality of at least one of magnetic beads, paramagnetic beads, and magnetically attractive beads.