Abstract: A device for assisting in fluid mixing within microfluidic sized structures. Chemicals and other biological specimens are exposed to a small volume of reagent, and said reagent is delivered to said specimens by a novel mixing technique, thus shortening overall process time.

Abstract: A method and apparatus are disclosed for controlling a flow rate of a fluid sample having an unknown or variable viscosity. The fluid sample is provided as a first fluid flow to a microfluidic channel. A second fluid is provided to the channel as a sheath around the first fluid. In one embodiment, the second fluid is injected between the first fluid flow and an internal surface of the channel. In another embodiment, the second fluid completely circumscribes the first fluid as a parallel or sheath flow. The second fluid has a known viscosity selected for achieving a flow rate. The first fluid flows at the same rate as the achieved flow rate of the second fluid.

Abstract: A device for mixing separate distinct fluids within a microfluidic device to form a substantially homogeneous flow stream. The device is generally circular-shaped and contains no moving parts, and is capable of mixing both serial and laminar flow streams.

Abstract: A device for analyzing sample solutions such as whole blood based on coagulation and agglutination which requires no external power source or moving parts to perform the analysis.

Abstract: A device for generating a stable concentration gradient in a microfluidic channel. A solution of a given concentration of a soluble compound and a diluting solution are co-delivered into a microfluidic channel. By varying the flow rates of the two solutions, the concentration of the soluble compound can be varied as a function of the length of the channel.

Abstract: Micropumps fabricated by micromachining techniques and employing fixed or no-moving-parts valves. As one aspect of the invention, a laser-assisted chemical etching technique is employed for providing smooth-walled, curved configuration necessary to obtain the desired flow characteristics of the valves that are used in conjunction with the micropump.