Abstract: An example microfluidic device includes a microfluidic network through which operational fluid is to flow and a droplet ejector. The microfluidic device includes a drive fluid storage volume to contain drive fluid, the drive fluid storage volume connected in series between the microfluidic network and the droplet ejector. When the drive fluid is ejected from the droplet ejector, the operational fluid is drawn through the microfluidic network.

Abstract: A fluid circulation and ejection system may include a microfluidic die, a single orifice fluid ejector having a drive chamber in the microfluidic die and a pressurized fluid source remote from the microfluidic die to create a pressure gradient across the drive chamber to circulate fluid across the drive chamber.

Abstract: A device includes: a die including a microfluidic device; a polymer substrate formed around the die; and a separate fluid manifold attached to the polymer substrate over the die and on a same side of the substrate as the die, the manifold to deliver fluid to the die.

Abstract: A biological fluid dilution device can include a syringe body including a diluent chamber at a front end of the syringe body and a piston tube at a rear end of the syringe body. The diluent chamber can be partially filled with a diluent fluid. A moveable piston can be slidably engaged in the piston tube and form a fluid-tight seal with an interior surface of the piston tube. The moveable piston can include a metering groove to contain a precise volume of a biological fluid between the metering groove and the interior surface of the piston tube. A biological fluid inlet on the piston tube can be capable of delivering the biological fluid to the metering groove. The moveable piston can be slidable toward to diluent chamber to introduce the biological fluid in the metering groove into the diluent chamber.

Abstract: A fluid delivery system, in an example, may include a substrate and a lid coupled to a first side of the substrate wherein the substrate comprises a number of fluidic feed slots fluidically coupling the substrate to a die coupled to a second surface of the substrate and wherein the lid includes at least one main chamber to house at least one type of fluid, at least one overflow reservoir with the overflow reservoir fluidically coupled to the main chamber via an overflow channel, and wherein the overflow channel comprises a capillary pinch point to hold an amount of printing fluid within the main chamber.

Abstract: A fluidic die includes a fluid channel layer including at least one fluid channel defined along a length of the fluid ejection device. The fluidic die also includes an interposer layer coupled to the fluid channel layer. The interposer layer includes a number of inlet ports defined in the interposer layer to fluidically couple the at least one channel layer to a fluid source, and a number of outlet ports defined in the interposer layer to fluidically couple the at least one channel layer to the fluid source.

Abstract: A fluidic die may include a fluid channel layer defining a number of fluid channels therein, a slot layer disposed on a side of the fluid channel layer, and a first fluid slot and a second fluid slot defined in the slot layer. At least one of the fluid channels fluidically couples the first fluid slot to the second fluid slot. The first fluid slot and the second fluid slot are defined in the slot layer along a length of the fluidic die.

Abstract: An assembly, in an example, may include at least one die, a substrate comprising at least one electrical trace, a lid coupled to a first side of the substrate to contain an amount of fluid between the substrate and lid, and an adhesive film coupled to a second side of the substrate to protect the at least one electrical trace wherein the lid further comprises a main chamber for each of at least two distinct fluids and an overflow chamber fluidically coupled to each of the main chambers via an overflow channel.

Abstract: A fluidic die may include a fluid channel layer defining a number of fluid channels therein, a slot layer disposed on a side of the fluid channel layer, and a first fluid slot and a second fluid slot defined in the slot layer. At least one of the fluid channels fluidically couples the first fluid slot to the second fluid slot. The first fluid slot and the second fluid slot are defined in the slot layer along a length of the fluidic die.

Abstract: A fluid circulation and ejection system may include a microfluidic die, a single orifice fluid ejector having a drive chamber in the microfluidic die and a pressurized fluid source remote from the microfluidic die to create a pressure gradient across the drive chamber to circulate fluid across the drive chamber.

Abstract: Examples herein involve amplification and detection of nucleic acids using a microfluidic reaction chamber. An example apparatus includes a reaction-chamber circuit to process a reagent and a biologic sample for amplification of nucleic acids. The apparatus further includes a plurality of capillaries to pass the reagent and the biologic sample through the microfluidic reaction chamber. A valve control system may selectively control each of a plurality of valves to cause the reagent and the biologic sample to selectively move through the microfluidic reaction chamber for the amplification of the nucleic acids according to a particular timing sequence.

Abstract: An example device includes a first chamber to contain a first fluid and a second chamber to contain a second fluid. The first chamber includes a first fluid outlet, and a first bubbler to ingest bubbles into the first chamber when pressure in the first chamber overcomes a first bubble pressure of the first bubbler. The second chamber includes a second fluid outlet, and a second bubbler to ingest bubbles into the second chamber when pressure in the first chamber overcomes a second bubble pressure of the second bubbler. An outlet node is fluidly connected to the first fluid outlet and the second fluid outlet. The outlet node draws the first fluid from the first chamber when the first bubbler ingests bubbles, and sequentially draws the second fluid from the second chamber when the second bubbler ingests bubbles.

Abstract: A fluid ejection device includes a fluid ejection assembly including a fluid ejection die, and a service assembly to be rotated to different positions relative to the fluid ejection assembly for different service operations of the fluid ejection die.

Abstract: An assembly, in an example, may include at least one die, a substrate comprising at least one electrical trace, a lid coupled to a first side of the substrate to contain an amount of fluid between the substrate and lid, and an adhesive film coupled to a second side of the substrate to protect the at least one electrical trace wherein the lid further comprises a main chamber for each of at least two distinct fluids and an overflow chamber fluidically coupled to each of the main chambers via an overflow channel.

Abstract: A die may, in an example, include at least one cross-die recirculation channel formed into the die to recirculate an amount of printing fluid therethrough, the cross-die recirculation channel including a first-sized inlet port and a first-sized outlet port formed on a first side of the die, at least one chamber recirculation channel formed into the die and fluidically coupled to the cross-die recirculation channel to recirculate an amount of printing fluid therethrough, the chamber recirculation channel including a second-sized inlet port and a second-sized outlet port, at least one pump formed within the chamber recirculation channel to recirculate the amount of printing fluid therethrough.

Abstract: In one example in accordance with the present disclosure, a fluidic ejection die is described. The die includes an array of nozzles. Each nozzle includes an ejection chamber and an opening. A fluid actuator is disposed within the ejection chamber. The fluidic ejection die also includes an army of passages, formed in a substrate, to deliver fluid to and from the ejection chamber. The fluidic ejection die also includes an army of enclosed cross-channels. Each enclosed cross-channel of the army of enclosed cross-channels is fluidly connected to a respective plurality of passages of the array of passages.

Abstract: A fluid ejection assembly includes a fluid ejection die, and a body supporting the fluid ejection die, with the body having a fluid chamber communicated with the fluid ejection die and including a receptacle to receive a removable fluid supply, with the receptacle having a fluid port communicated with the fluid chamber through the body.

Abstract: An example microfluidic device includes a microfluidic network through which operational fluid is to flow and a droplet ejector. The microfluidic device includes a drive fluid storage volume to contain drive fluid, the drive fluid storage volume connected in series between the microfluidic network and the droplet ejector. When the drive fluid is ejected from the droplet ejector, the operational fluid is drawn through the microfluidic network.

Abstract: An example device includes a first chamber to contain a first fluid and a second chamber to contain a second fluid. The first chamber includes a first fluid outlet, and a first bubbler to ingest bubbles into the first chamber when pressure in the first chamber overcomes a first bubble pressure of the first bubbler. The second chamber includes a second fluid outlet, and a second bubbler to ingest bubbles into the second chamber when pressure in the first chamber overcomes a second bubble pressure of the second bubbler. An outlet node is fluidly connected to the first fluid outlet and the second fluid outlet. The outlet node draws the first fluid from the first chamber when the first bubbler ingests bubbles, and sequentially draws the second fluid from the second chamber when the second bubbler ingests bubbles.

Abstract: In one example in accordance with the present disclosure, a fluidic ejection die is described. The die includes an array of nozzles. Each nozzle includes an ejection chamber and an opening. A fluid actuator is disposed within the ejection chamber. The fluidic ejection die also includes an array of passages, formed in a substrate, to deliver fluid to and from the ejection chamber. The fluidic ejection die also includes an array of enclosed cross-channels. Each enclosed cross-channel of the array of enclosed cross-channels is fluidly connected to a respective plurality of passages of the array of passages.