Designs of a digital microfluidic devices are described comprising droplet control electrodes and heating electrodes that have effects in the regions for droplet manipulations. Specifically, the digital microfluidic device comprises a first substrate having liquid control electrodes for droplet control and a second substrate having heating electrodes for temperature control. Shielding electrodes are disposed on the second substrate to ensure that the heating electrodes can control the digital microfluidic device to a desired temperature profile without interfering the droplet operations such as transport, merging/mixing, splitting, particle distribution, etc.

The present invention generally relates to emulsions, and more particularly, to multiple emulsions. In one aspect, multiple emulsions are formed by urging a fluid into a channel, e.g., by causing the fluid to enter the channel as a jet. Side channels can be used to encapsulate the fluid with a surrounding fluid. In some cases, multiple fluids may flow through a channel collinearly before multiple emulsion droplets are formed. The fluidic channels may also, in certain embodiments, include varying degrees of hydrophilicity or hydrophobicity. As examples, the fluidic channel may be relatively hydrophilic upstream of an intersection (or other region within the channel) and relatively hydrophobic downstream of the intersection, or vice versa. In some cases, the average cross-sectional dimension may change, e.g., at an intersection. For instance, the average cross-sectional dimension may increase at the intersection. Surprisingly, a relatively small increase in dimension, in combination with a change in hydrophilicity of the fluidic channel, may delay droplet formation of a stream of collinearly-flowing multiple fluids under certain flow conditions; accordingly, the point at which multiple emulsion droplets are formed can be readily controlled within the fluidic channel. In some cases, the multiple droplet may be formed from the collinear flow of fluids at (or near) a single location within the fluidic channel. In addition, unexpectedly, systems such as those described herein may be used to encapsulate fluids in single or multiple emulsions that are difficult or impossible to encapsulate using other techniques, such as fluids with low surface tension, viscous fluids, or viscoelastic fluids. Other aspects of the invention are generally directed to methods of making and using such systems, kits involving such systems, emulsions created using such systems, or the like.

The present invention relates to the use of amphipathic polymers to enhance lateral flow and reagent mixing on assay devices. More specifically, the invention relates to use of an amphipathic polymer in assay methods including a device for determining the concentration of lipids in blood serum or plasma.

Fluidic devices and methods associated with mixing of fluids in fluidic devices are provided. In some embodiments, a method may involve the mixing of two or more fluids in a channel segment of a fluidic device. The fluids may be in the form of, for example, at least first, second and third fluid plugs, composed of first, second, and third fluids, respectively. The second fluid may be immiscible with the first and third fluids. In certain embodiments, the fluid plugs may be flowed in series in the channel segment, e.g., in linear order, causing the first and third fluids to mix without the use of active components such as mixers. The mixing of fluids in a channel segment as described herein may allow for improved performance and simplification in the design and operations of fluidic devices that rely on mixing of fluids.

Disclosed herein are apparatuses and methods for conducting multiple simultaneous micro-volume chemical and biochemical reactions in an array format. In one embodiment, the format comprises an array of microholes in a substrate. Besides serving as an ordered array of sample chambers allowing the performance of multiple parallel reactions, the arrays can be used for reagent storage and transfer, library display, reagent synthesis, assembly of multiple identical reactions, dilution and desalting. Use of the arrays facilitates optical analysis of reactions, and allows optical analysis to be conducted in real time. Included within the invention are kits comprising a microhole apparatus and a reaction component of the method(s) to be carried out in the apparatus.

Fluidic devices and methods associated with mixing of fluids in fluidic devices are provided. In some embodiments, a method may involve the mixing of two or more fluids in a channel segment of a fluidic device. The fluids may be in the form of, for example, at least first, second and third fluid plugs, composed of first, second, and third fluids, respectively. The second fluid may be immiscible with the first and third fluids. In certain embodiments, the fluid plugs may be flowed in series in the channel segment, e.g., in linear order, causing the first and third fluids to mix without the use of active to components such as mixers. The mixing of fluids in a channel segment as described herein may allow for improved performance and simplification in the design and operations of fluidic devices that rely on mixing of fluids.

Devices, systems, and their methods of use, for sorting or separating magnetic particles are provided. A magnetic source is disposed adjacent a flow path and exerts a magnetic field on magnetic particles in order to separate particles.

The present invention generally relates to emulsions, and more particularly, to double and other multiple emulsions. Certain aspects of the present invention are generally directed to the creation of double emulsions and other multiple emulsions at a common junction of microfluidic channels. In some cases, the microfluidic channels at the common junction may have substantially the same hydrophobicity. In one set of embodiments, a device may include a common junction of six or more channels, where a first fluid flows through one channel, a second fluid flows through two channels, and a third or carrying fluid flows through two more channels, such that a double emulsion of a first droplet of the first fluid, contained in a second droplet of the second fluid, contained by the carrying fluid, flows away from the common junction through a sixth channel. Other aspects of the invention are generally directed to methods of making and using such systems, kits involving such systems, emulsions created using such systems, or the like.

A method and an array filling system for loading a plurality of disparate sample containers, the sample containers comprising an integral structure. Each receptacle is characterized by a hydrophilic surface,, and the receptacles are separated by a hydrophobic surface. The system has a liquid transfer device capable of holding liquid and adapted for motion to cause sequential communication of liquid held in the liquid transfer device with successive receptacles of the array by dragging the liquid across the hydrophobic surface.

A microfluidic device having hydrophobic and hydrophilic regions and a method of manufacture thereof are provided. The microfluidic device may include one or more channels formed using a short-pulse laser that are configured for separation or mixing of fluids. The microfluidic device may further include hydrophilic or hydrophobic surfaces configured to aid in the separation or mixture of fluids. The short-pulse laser may be a femtosecond laser.