| abstract |
A microvalve and micropump, which in certain embodiments is configured as a rotary planar peristaltic micropump (RPPM). In certain embodiments, the RPPM includes a circumferential microfluidic channel with, for example, a square or round cross-section in a flexible, elastomeric substrate. In specific embodiments, a plurality of spherical balls rotating in a circle above the channel produces one or more compression zones in the substrate that occlude the channel and force the fluid to flow along the channel. The balls in turn are held in position by a loose cage structure and driven in a circle by a rotating disk of flexible elastomer. The combination of matched elastic properties of the substrate and the disk and the mechanical rotation of the disk causes the balls to rotate above the circular channel without slipping, and hence produces the travelling compression zones that occlude the channel and force the fluid to flow. In another embodiment, the balls can be replaced by rollers. In yet another embodiment, the pump can be incorporated into a recirculating mixer that homogenizes a fluid in a tube or channel whose concentration of different substances varies along the length of the tube or channel. In yet another embodiment, the pump and mixing capabilities of the invention are combined with remotely controlled valves to create a microformulator that can combine different solutions in known and carefully controlled nanoliter to microliter volumes and homogenize the resulting mixture to produce quickly a small volume of solution of known concentrations. |