Microfluidic systems and methods for arranging a set of objects. In an exemplary method, the set of objects may be transported in carrier fluid along a microfluidic channel structure having a reformatting zone including an object-accessible region and at least one object-excluding region. A portion of the carrier fluid may be moved from the object-accessible region to the at least one object-excluding region in an upstream section of the reformatting zone, to reduce a spacing of objects of the set. The portion of the carrier fluid may be directed into the object-accessible region from the at least one object-excluding region in a downstream section of the reformatting zone, to increase a spacing of objects of the set. The steps of moving and directing in combination may increase the spacing between objects disproportionately for a subset of the objects that are closest to one another.

The present disclosure provides methods for carrying out Romanowsky-type stains, specifically Wright-Giemsa and May-Grünwald stains, quickly and efficiently. The methods greatly reduce the overall amount of time required to complete a Wright-Giemsa stain or a May-Grünwald stain of sufficient quality on a biological sample. The subject methods can be applied to both manual and automated staining procedures.

The invention generally relates to methods and devices for transferring a sample into a cartridge for processing. Methods of the invention include providing a vessel containing a sample, coupling the sample to a cartridge configured to process the sample at an interface, in which the interface is configured to provide communication between the vessel and the cartridge, introducing a fluid, capture particles, or both from the cartridge into the vessel, and transferring the sample, fluid, and capture particles from the vessel and into the cartridge for processing.

The present invention comprises methods and systems that use acoustic radiation pressure.

Disclosed herein is a method and system for concentrating analyte from large sample solutions using a combination of magnetic microparticles on a digital microfluidic device using virtual channels. Virtual channels are produced by applying voltages to a series of driving electrodes of the DMF that connect a reservoir of solution situated just outside of the DMF device to a fluid exit location. The magnetic microparticles are first exposed to a liquid sample containing the analyte whereupon analytes are bound by analyte specific receptors on the microparticles. By flowing these solutions of magnetic particles through virtual channels in DMF device, large volumes can be processed, regardless of the total capacity of the DMF. Engaging a magnet underneath the DMF device while a suspension of magnetic microparticles is flowed through the virtual channel causes the microparticles to become immobilized and the supernatant solution is removed. The isolated magnetic microparticles can then be resuspended in a much smaller volume and further processed on the DMF device for whatever application, thereby significantly increasing the concentration of the analytes in the small droplets compared to the original liquid solution.

Embodiments described herein generally relate to apparatuses, cartridges, and pumps for peristaltic pumping of fluids and associated methods, systems, and devices. The pumping of fluids is, in certain cases, an important aspect of a variety of applications, such as bioanalytical applications (e.g., biological sample analysis, sequencing, identification). The inventive features described herein may, in some embodiments, provide an ability to pump fluids in ways that combine certain advantages of robotic fluid handling systems (e.g., automation, programmability, configurability, flexibility) with certain advantages of microfluidics (e.g., small fluid volumes with high fluid resolution, precision, monolithic consumables, limiting of the wetting of components to consumables).

The present invention relates to a system and method for moving samples, such as fluid, within a microfluidic system using a plurality of gas actuators for applying pressure at different locations within the microfluidic. The system includes a substrate which forms a fluid network through which fluid flows, and a plurality of gas actuators integral with the substrate. One such gas actuator is coupled to the network at a first location for providing gas pressure to move a microfluidic sample within the network. Another gas actuator is coupled to the network at a second location for providing gas pressure to further move at least a portion of the microfluidic sample within the network. A valve is coupled to the microfluidic network so that, when the valve is closed, it substantially isolates the second gas actuator from the first gas actuator.

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.

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.

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.