Abstract: A microfluidic reaction system may include a microfluidic die having a microfluidic volume, a port connected to the microfluidic volume for receiving a fluid and a freeze-dried reaction agent coating at least a portion of the microfluidic volume.

Abstract: A biological component concentration fluid assembly includes magnetizing microparticles that are surface-activated to bind with (or are bound to) a biological component; a multi-fluid density gradient column with a first fluid layer, a second fluid layer, and a third fluid layer; and a magnet to attract and draw the magnetizing microparticles from the first fluid layer, through the second fluid layer, and into the third fluid layer. The first fluid layer has a first fluid density, and a second fluid layer has a second fluid density that is greater than the first fluid density, and is positioned beneath the first fluid layer. A third fluid layer has a third fluid density that is greater than the second fluid density and is positioned beneath the second fluid layer. The second and third fluid layers in this example are formulated to interact with the surface of the magnetizing microparticles.

Abstract: A microfluidic coagulation analysis method includes introducing a fluid sample into a measurement device including a pinch point that includes a microfluidic channel of substantially consistent width and height connecting a slot and a chamber. The at least one pinch point permits passage of the fluid sample from the slot to the chamber. The method further includes measuring, with a sensor in or near the pinch point, transits of individual cells in the sample passing through the at least one pinch point, and computing, at least in part with a processor, at least one metric indicative of a time period during which the flow of the sample transitions from substantially fluid flow to substantial cessation of flow.

Abstract: A microfluidic blood coagulation testing die includes a substrate, a slot in the substrate permitting entry of a sample of blood, a chamber in the substrate for collection of cells in the sample, and a pinch point that permits passage of sample from slot to chamber. The die includes a sensor in or near the at least one pinch point to test sample passing through the at least one pinch point. Activator, such as freeze-dried coagulation-initializing tissue factor, coats at least a portion of the interior surface of the slot, pinch point, and chamber.

Abstract: A microfluidic reaction system may include a microfluidic die having a microfluidic volume, a port connected to the microfluidic volume for receiving a fluid and a freeze-dried reaction agent coating at least a portion of the microfluidic volume.