Microfluidic structures and methods for manipulating fluids, fluid components, and reactions are provided. In one aspect, such structures and methods can allow production of droplets of a precise volume, which can be stored/maintained at precise regions of the device. In another aspect, microfluidic structures and methods described herein are designed for containing and positioning components in an arrangement such that the components can be manipulated and then tracked even after manipulation. For example, cells may be constrained in an arrangement in microfluidic structures described herein to facilitate tracking during their growth and/or after they multiply.

A pierceable cap 11 may be used for containing sample specimens. The pierceable cap 11 may prevent escape of sample specimens before transfer with a transfer device 43. The pierceable cap 11 may fit over a vessel 21. An access port in the shell of the pierceable cap 11 may allow passage of a transfer device 43 through the pierceable cap 11. At least one frangible layer 215, 216 may be configured with cross slits 506 in a particular cross slit geometry. The cross slits 506 may contain an openable portion 644 or be covered by a thin membrane 645. The shell 610 and frangible layer(s) 215, 216 may be integrated into a one piece cap 601, or be separate components 634. The membrane on which the cross slits 506 are placed can be flat or contoured to guide the transfer device 43 to the cross slits 506.

Fluid storage containers and analysis cartridges for use in assay processes are presented. In addition, systems comprising such storage containers and analysis cartridges and methods of using such containers and cartridges are presented as well. In specific embodiments, fluid storage containers are configured to be coupled to analysis cartridges in a first stage and a second stage.

Constricted nanochannel devices suitable for use in analysis of macromolecular structure, including DNA sequencing, are disclosed. Also disclosed are methods for fabricating such devices and for analyzing macromolecules using such devices.

Methods are provided for separating magnetically responsive beads from a droplet in a droplet actuator. Droplet operations electrodes and a magnet are arranged in a droplet actuator to manipulate a bead-containing droplet and position it relative to a magnetic field region that attracts the magnetically responsive beads. The droplet operations electrodes are operated to control the droplet shape and transport it away from the magnetic field region to form a concentration of beads in the droplet. The continued transport of the droplet away from the magnetic field causes the concentration of beads to break away from the droplet to yield a small, concentrated bead-containing droplet immobilized by the magnet.

Disclosed here are pipette tips useful for acquiring or dispelling liquids, and include one or more design that may increase fluid delivery precision and/or accuracy, and may reduce certain repetitive motions.

Various systems, methods, and devices are provided for focusing particles suspended within a moving fluid into one or more localized stream lines. The system can include a substrate and at least one channel provided on the substrate having an inlet and an outlet. The system can further include a fluid moving along the channel in a laminar flow having suspended particles and a pumping element driving the laminar flow of the fluid. The fluid, the channel, and the pumping element can be configured to cause inertial forces to act on the particles and to focus the particles into one or more stream lines.

An apparatus for preparing a reagent solution includes an enclosure and a container disposed within the enclosure. The container defines an internal cavity having a compressible volume and defines a passage providing fluidic communication between the internal cavity and the exterior of the container. Optionally, a compressible member is disposed within the internal cavity. A reagent is disposed within the internal cavity.

Microfluidic pumps are provided that use electrowetting to manipulate the location of one or more droplets of a working fluid (e.g., water) in order to pump tears, blood, laboratory samples, carrier fluid, or some other payload fluid. The working fluid is separated from the payload fluid by one or more droplets of an isolating fluid that is immiscible with the working fluid. The working fluid is manipulated via electrowetting, by applying voltages to two or more electrodes, to repeatedly move back and forth. Forces, pressures, and/or fluid flows exerted by the working fluid are coupled to the payload fluid via the droplet(s) of isolation fluid and reed valves, diffuser nozzles, or other varieties of valve can act as flow-rectifying elements to convert the coupled forces into a net flow of the payload fluid through the pump.

An apparatus for preparing a reagent solution includes an enclosure and a container disposed within the enclosure. The container defines an internal cavity having a compressible volume and defines a passage providing fluidic communication between the internal cavity and the exterior of the container. Optionally, a compressible member is disposed within the internal cavity. A reagent is disposed within the internal cavity.