Abstract: Articles and methods for controlling flow in fluidic systems, especially in microfluidic systems, are provided. In one aspect, a microfluidic system described herein includes a configuration such that the actuation of a single valve can allow the switching of fluids from a first fluid path (e.g., a first channel section) to a second fluid path (e.g., a second channel section). This may be achieved, for example, by incorporating a valve with a first channel section, which may have a lower hydrodynamic resistance than a second channel section prior to actuation of the valve. Actuation of the valve can cause only the hydrodynamic resistance of the first channel section to increase, thereby redirecting fluid flow into the second channel section (which now has a relatively lower hydrodynamic resistance).

Abstract: 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.

Abstract: Methods for the detection of components from biological samples are provided. In certain aspects, the methods may be used to detect and/or quantify specific components in a biological sample, such as tumor cells (e.g., circulating tumor cells). Systems and devices for practicing the subject methods are also provided.

Abstract: Articles and methods for controlling flow in fluidic Systems, especially in microfluidic Systems, are provided. A microfluidic System includes a configuration such that the actuation of a single valve can allow the switching of fluids from a first fluid path (e.g., a first channel section) to a second fluid path (e.g., a second channel section). This may be achieved by incorporating a valve (38) with a first channel section (24), which may have a lower hydrodynamic resistance than a second channel section (28) prior to actuation of the valve. Actuation of the valve (38) can cause only the hydrodynamic resistance of the first channel section (24) to increase, thereby redirecting fluid flow into the second channel section (28) (which now has a relatively lower hydrodynamic resistance). The valve comprises a control channel (40) for introducing a positive or reduced pressure, and is adapted to modulate fluid flow in an adjacent channel section by constricting or expanding the channel section (24).

Abstract: The present invention generally relates to microfluidics, and to spray drying and other drying techniques. In some aspects, an article containing one or more channels or microfluidic channels is used to mix one or more fluids prior to spray drying. The mixing may occur immediately before the fluids are expelled through a nozzle or other opening into a drying region of the spray dryer. In one set of embodiments, for example, a first fluid is exposed to a second fluid, then the fluids are exposed to air or other gases before being expelled through a nozzle. In certain instances, the first fluid may contain a dissolved species that may precipitate upon exposure to the second fluid; such precipitation may occur immediately before expulsion through a nozzle or other opening, thereby resulting in controlled precipitation as part of the spray drying process.

Abstract: 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.

Abstract: Parallel uses of microfluidic methods and devices for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid are described. In some aspects, the present invention relates generally to flow-focusing-type technology, and also to microfluidics, and more particularly parallel use of microfluidic systems arranged to control a dispersed phase within a dispersant, and the size, and size distribution, of a dispersed phase in a multi-phase fluid system, and systems for delivery of fluid components to multiple such devices.

Abstract: The present invention is generally related to systems and methods for producing droplets. The droplets may contain varying species, e.g., for use as a library. In some cases, at least one droplet is used to create a plurality of droplets, using techniques such as flow-focusing techniques. In one set of embodiments, a plurality of droplets, containing varying species, can be divided to form a collection of droplets containing the various species therein. A collection of droplets, according to certain embodiments, may contain various subpopulations of droplets that all contain the same species therein. Such a collection of droplets may be used as a library in some cases, or may be used for other purposes.

Abstract: Methods for the detection of components from biological samples are provided. In certain aspects, the methods may be used to detect and/or quantify specific components in a biological sample, such as tumor cells (e.g., circulating tumor cells). Systems and devices for practicing the subject methods are also provided.

Abstract: Parallel uses of microfluidic methods and devices for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid are described. In some aspects, the present invention relates generally to flow-focusing-type technology, and also to microfluidics, and more particularly parallel use of microfluidic systems arranged to control a dispersed phase within a dispersant, and the size, and size distribution, of a dispersed phase in a multi-phase fluid system, and systems for delivery of fluid components to multiple such devices.

Abstract: The present invention is generally related to systems and methods for producing droplets. The droplets may contain varying species, e.g., for use as a library. In some cases, at least one droplet is used to create a plurality of droplets, using techniques such as flow-focusing techniques. In one set of embodiments, a plurality of droplets, containing varying species, can be divided to form a collection of droplets containing the various species therein. A collection of droplets, according to certain embodiments, may contain various subpopulations of droplets that all contain the same species therein. Such a collection of droplets may be used as a library in some cases, or may be used for other purposes.

Abstract: Methods and systems for manipulating drops in microfluidic channels are provided.

Abstract: The present invention generally relates to systems and methods for creating droplets. In one aspect, a plurality of droplets (27) is introduced into a continuous fluid stream (21) to cause the continuous fluid stream to form discrete droplets. In some cases, the droplets that are formed from the continuous fluid stream may be substantially monodisperse. The continuous fluid stream may, in some cases, be a jetting fluid stream flowing at a relatively high linear flow rate, and in certain embodiments, high rates of droplet formation from the jetting fluid may thereby be achieved. Additionally, certain aspects of the invention are generally directed to devices, such as microfluidic devices, able to form such droplets.

Abstract: The present invention generally relates to systems and techniques for manipulating fluids and/or making droplets. In certain aspects, the present invention generally relates to droplet production. The droplets may be formed from fluids from different sources. In one set of embodiments, the present invention is directed to a microfluidic device comprising a plurality of droplet-making units, and/or other fluidic units, which may be substantially identical in some cases. Substantially each of the fluidic units may be in fluidic communication with a different source of a first fluid and a common source of a second fluid, in certain embodiments. In one aspect, substantially the same pressure may be applied to substantially all of the different sources of fluid, which may be used to cause fluid to move from the different sources into the microfluidic device. In some cases, the fluids may interact within the fluidic units, e.g., by reacting, or for the production of droplets within the microfluidic device.

Abstract: The present invention provides a method for coating metal oxide on a PDMS surface. The method includes preparing a mixture that contains a sol-gel precursor, reacting the mixture to form a preconverted sol-gel precursor, where the preconverted sol-gel precursor does not diffuse into PDMS and is not in the form of a gel, forming a reactive PDMS surface, applying the preconverted sol-gel precursor onto the reactive PDMS surface, binding the preconverted sol-gel precursor to the re-active PDMS surface, and converting the bound preconverted sol-gel precursor to a metal oxide to form a metal oxide coating on the PDMS surface. The present invention also provides a PDMS microfluidic device where one or more channels of the microfluidic device is provided with a metal oxide coating covalently bound only on the surface of the one or more channels.

Abstract: This invention generally relates to particle-assisted nucleic acid sequencing. In some embodiments, sequencing may be performed in a microfluidic device, which can offer desirable properties, for example, minimal use of reagents, facile scale-up, and/or high throughput. In one embodiment, a target nucleic acid may be exposed to particles having nucleic acid probes. By determining the binding of the particles to the target nucleic acid, the sequence of the target nucleic acid (or at least a portion of the target nucleic acid) can be determined. The target nucleic acid may be encapsulated within a fluidic droplet with the particles having nucleic acid probes, in certain instances. In some cases, the sequence of the target nucleic acid may be determined, based on binding of the particles, using sequencing by hybridization (SBH) algorithms or other known techniques.

Abstract: The present invention generally relates to coating materials, including photoactive coating materials. In some aspects of the invention, a sol-gel is provided that can be formed as a coating on a microfluidic channel. One or more portions of the sol-gel can be reacted to alter its hydrophobicity, in some cases. For instance, in one set of embodiments, a portion of the sol-gel may be exposed to light, such as ultraviolet light, which can be used to induce a chemical reaction in the sol-gel that alters its hydrophobicity. In one set of embodiments, the sol-gel can include a photoinitiator, that upon exposure to light, produces radicals. Optionally, the photoinitiator may be conjugated to a silane or other material within the sol-gel. The radicals so produced may be used to cause a polymerization reaction to occur on the surface of the sol-gel, thus altering the hydrophobicity of the surface. In some cases, various portions may be reacted or left unreacted, e.g.

Abstract: This invention generally relates to particle-assisted nucleic acid sequencing. In some embodiments, sequencing may be performed in a microfluidic device, which can offer desirable properties, for example, minimal use of reagents, facile scale-up, and/or high throughput. In one embodiment, a target nucleic acid may be exposed to particles having nucleic acid probes. By determining the binding of the particles to the target nucleic acid, the sequence of the target nucleic acid (or at least a portion of the target nucleic acid) can be determined. The target nucleic acid may be encapsulated within a fluidic droplet with the particles having nucleic acid probes, in certain instances. In some cases, the sequence of the target nucleic acid may be determined, based on binding of the particles, using sequencing by hybridization (SBH) algorithms or other known techniques.

Abstract: The present invention generally relates to coating materials, including photoactive coating materials. In some aspects of the invention, a sol-gel is provided that can be formed as a coating on a microfluidic channel. One or more portions of the sol-gel can be reacted to alter its hydrophobicity, in some cases. For instance, in one set of embodiments, a portion of the sol-gel may be exposed to light, such as ultraviolet light, which can be used to induce a chemical reaction in the sol-gel that alters its hydrophobicity. In one set of embodiments, the sol-gel can include a photoinitiator, that upon exposure to light, produces radicals. Optionally, the photoinitiator may be conjugated to a silane or other material within the sol-gel. The radicals so produced may be used to cause a polymerization reaction to occur on the surface of the sol-gel, thus altering the hydrophobicity of the surface. In some cases, various portions may be reacted or left unreacted, e.g.

Abstract: The present invention generally relates to fluidics and microfluidics and, in particular, to creating droplets in a fluidic system. In some aspects, the present invention is generally directed to systems and methods for splitting a parent droplet into two or more droplets, e.g., by urging the parent droplet towards an obstacle to split the parent droplet. In some cases, the parent droplet is split into at least first and second droplets which each are directed to separate channels. In some cases, the channels may be constructed and arranged such that the droplet velocities of the first and second droplets are substantially the same as the velocity of the parent droplet. In some cases, such droplets may be repeatedly split, e.g., a parent droplet is divided into 2 daughter droplets, then each droplet split again, etc., for example, such that one parent droplet may eventually be split into 22, 23, 24, 25, 26, etc. daughter droplets. In some cases, the daughter droplets may be substantially monodisperse.