Devices and methods are provided for spotting an array with fluid. Arrays produced by such methods are also provided. In one aspect of the invention, a spotter device for spotting a plurality of fluids into an array is described, the spotter device comprising a plurality of reservoirs provided in a first configuration, each reservoir holding its respective fluid, a print head having a plurality of positions provided in a second configuration, the second configuration being different from the first configuration, a plurality of tubes, each tube configured to provide fluid communication from a reservoir at a first end of the tube to a position in the print head at the second end of the tube, and a pump for pumping fluid through the tubes from the reservoir to the print head.

A system includes a droplet actuator having a droplet-operation gap between top and bottom substrates, a reservoir(s) external to and coupled to the droplet actuator, the reservoir(s) sized for a large-volume fluid, and pressure source(s) external to the droplet actuator and coupled to the at least one reservoir. Operation of the system includes filling the reservoir(s) with a large volume of fluid(s), dispensing droplet(s) of the fluid(s) to the droplet-operation gap using the pressure source(s) as part of performing a droplet operation(s). Movement of the droplet(s) may be effectuated by activating the droplet actuator.

Devices and systems for droplet generation and methods for generating droplets are described. In an embodiment, the devices and systems include a capillary configured to eject a droplet, such as in response to a voltage applied to an end of the capillary. In an embodiment, the devices and systems include a moveable stage configured to carry a multi-well plate and move the stage relative to the capillary such that the ejected droplet is selectively received by a well of the multi-well plate carried by the moveable stage.

A fluid dispenser having a casing (E) provided with a dispenser head (11); and a refill cartridge (C) that includes a fluid reservoir (R). The refill cartridge (C) is axially insertable into the casing (E) in such a manner as to connect the fluid reservoir (R) to the dispenser head (11). The refill cartridge (C) and the casing (E) are provided with a connection mechanism (17, 253) that connects the refill cartridge (C) in the casing (E) by screw-fastening, so as to bring the fluid reservoir (R) into leaktight contact with the dispenser head (11). The movement, after screw-fastening, of the refill cartridge (C) in the casing (E) towards the dispenser head (11) delivers the fluid to the dispenser head (11).

Arrays of droplet-on-demand dispensers are controlled by a row-column addressing scheme that can reduce the number of on-chip address lines, thereby making it feasible to construct large dispenser arrays. Decoders are used to further reduce the number of control lines that select a specific address line. A microfluidic logic controller includes row-select lines, each coupled to dispensers disposed on the same row, and column-select lines, each coupled to dispensers disposed on the same column such that each dispenser is associated with a unique row-column address. A logic circuit can actuate a dispenser only if the logic circuit receives signals from both of the row-select line and the column-select line corresponding to the row-column address of the selected dispenser. Reagents can be dispensed from the dispenser array, thereby allowing for rapid formatting of a reagent library into microfluidic droplets.

A droplet dispenser comprises a chamber (3) with a fluid inlet valve (2) and a fluid outlet valve (4). The chamber (3) is arranged such that the volume of the chamber may be varied in use to cause fluid to be alternately drawn in to the chamber (3) through the inlet valve (2) then subsequently expelled from the chamber through the outlet valve (4) to dispense a droplet. The droplet dispenser is capable of dispensing from an open reservoir and one may change the dispensed drop volume simply and easily. The droplet dispenser can also handle liquids which are normally seen as difficult to dispense, such as cyanoacrylate adhesives.

A chemical synthesis platform based on a particularly simple chip is described herein, where reactions take place atop a hydrophobic substrate patterned with a circular hydrophilic liquid trap. The overall supporting hardware (heater, rotating carousel of reagent dispensers, etc.) can be packaged into a very compact format (about the size of a coffee cup). We demonstrate the consistent synthesis of [.sup.18F]fallypride with high yield, and show that protocols optimized using a high-throughput optimization platform we have developed can be readily translated to this device with no changes or reoptimization.

A method includes dispensing a liquid from a dispenser having a first piston channel and a first nozzle channel that is non-parallel to the first piston channel and is connected to the first piston channel at a first intersection. The dispenser includes a first piston configured to slide within the first piston channel; a first nozzle coupled with the first nozzle channel; a first valve located between a dispensing-liquid reservoir and the first intersection; and a second valve located between the first intersection and the first nozzle. Dispensing the liquid from the first dispenser includes pulling the first piston to initiate flow of a liquid in the dispensing-liquid reservoir to the first intersection; and subsequent to pulling the first piston, pushing the first piston to initiate flow of the liquid in the first intersection to the first nozzle so that the liquid is dispensed from the first nozzle.

A microfluidic device comprising at least one isolation unit and at least one capillary valve. The at least one isolation unit has at least one chamber. The at least one chamber configured to receive at least two different aqueous solutions. The at least one capillary valve is configured to allow for the at least two different aqueous solutions to be introduced into the at least one chamber without mixing prior to entering the at least one chamber based at least in part on pressure levels of the at least two different aqueous solutions.

A droplet dispenser comprises a chamber (3) with a fluid inlet valve (2) and a fluid outlet valve (4). The chamber (3) is arranged such that the volume of the chamber may be varied in use to cause fluid to be alternately drawn in to the chamber (3) through the inlet valve (2) then subsequently expelled from the chamber through the outlet valve (4) to dispense a droplet. The droplet dispenser is capable of dispensing from an open reservoir and one may change the dispensed drop volume simply and easily. The droplet dispenser can also handle liquids which are normally seen as difficult to dispense, such as cyanoacrylate adhesives.