Abstract: A centrifugal microfluidic technique for heat treating emulsion-divided independent reaction volumes (IRVs) within a centrifugal microfluidic chip, and displacing the emulsion into a monolayer presentation chamber (pc) for imaging. A deep treatment chamber (tc) is provided for the heat treatment, a nozzle having a hydrodynamic radius for forming the IRVs is provided for injecting a sample for the IRVs into the tc filled with a dense immiscible medium. The tc is adjacent a heat controlled element for collectively heat treating the IRVs within the tc, where the IRVs form a 3d packing arrangement. The tc is coupled to a presentation chamber (pc) by an opening through which the IRVs can be selectively displaced without collapsing. The pc is adjacent a window transparent to a wavelength for inspecting the pc.

Abstract: A technique for supplying droplet content of an oil-encapsulated (OE) digital microfluidic (D?F) network to a region that is sensitive to oil contact involves sealing off a boundary surrounding the sensitive region with a volume of liquid that is miscible with payload of the OE-droplets. The sensitive region may be an opening to a microfluidic channel, or a sensor surface. The sealing off may be provided by transporting an unencapsulated droplet over the OE-D?F chip, either from a reservoir prior to oil encapsulation of the reservoir, or from a non-oil encapsulated reservoir; or by injecting the liquid into the microfluidic channel. A suitable treatment of the boundary may anchor the liquid to the boundary, and prevent removal by ordinary OE-D?F operations. A remainder of the surfaces of unit cells the D?F chip may provide higher droplet contact angle.

Abstract: A centrifugal microfluidic chip is provided that allows an on-chip chamber to provide humidification control, or more generally, gas composition control, to another chamber of the chip. This allows for microfluidic incubation using low-cost and efficient centrifugal devices such as multi-port pneumatic chip controllers, single or multi-port pneumatic slip rings, and articulated centrifugal blades with a pneumatic slip ring. The device may be used for cell culturing, microorganism testing, or production of chemical species from biological samples with a controlled microenvironment.

Abstract: A plasmon resonance system, instrument, cartridge, and methods for analysis of analytes is disclosed. A PR system is provided that may include a DMF-LSPR cartridge that may support both digital microfluidic (DMF) capability and localized surface plasmon resonance (LSPR) capability for analysis of analytes. In some examples, the DMF portion of the DMF-LSPR cartridge may include an electrode arrangement for performing droplet operations, whereas the LSPR portion of the DMF-LSPR cartridge may include an LSPR sensor. In other examples, the LSPR portion of the DMF-LSPR cartridge may include an in-line reference channel, wherein the in-line reference channel may be a fluid channel including at least one functionalized LSPR sensor (or sample spot) and at least one non-functionalized LSPR sensor (or reference spot). Additionally, methods of using the PR system for analysis of analytes are provided.

Abstract: A plasmon resonance system, instrument, cartridge, and methods for analysis of analytes is disclosed. A PR system is provided that may include a DMF-LSPR cartridge that may support both digital microfluidic (DMF) capability and localized surface plasmon resonance (LSPR) capability for analysis of analytes. In some examples, the DMF portion of the DMF-LSPR cartridge may include an electrode arrangement for performing droplet operations, whereas the LSPR portion of the DMF-LSPR cartridge may include an LSPR sensor. In other examples, the LSPR portion of the DMF-LSPR cartridge may include an in-line reference channel, wherein the in-line reference channel may be a fluid channel including at least one functionalized LSPR sensor (or sample spot) and at least one non-functionalized LSPR sensor (or reference spot). Additionally, methods of using the PR system for analysis of analytes are provided.

Abstract: The present invention relates into a device and method for controlling distribution of superparamagnetic nanoparticles (NPs) in a microfluidic chamber. By applying a strong magnetic field, localization of the NPs to inter-pillar spaces between soft magnetic coated micropillars is demonstrated, even with a modest fluid flow across the inter-pillar space. Flow splitting techniques are also provided to force particles to reliably interact with the NPs, specifically by using a Brevais lattice with a primative vector of 1°-15° with respect to flow direction. The pillars may have non-circular cross-sectional shape and be arranged to direct NP clouds more effectively. An array of the pillars has multiple axes for rotating NP cloud distributions in multiple orientations, allowing for a rotating magnetic field to move the NP cloud for mixing a fluid that is otherwise stationary.

Abstract: A plasmon resonance system, instrument, cartridge, and methods for analysis of analytes is disclosed. A PR system is provided that may include a DMF-LSPR cartridge that may support both digital microfluidic (DMF) capability and localized surface plasmon resonance (LSPR) capability for analysis of analytes. In some examples, the DMF portion of the DMF-LSPR cartridge may include an electrode arrangement for performing droplet operations, whereas the LSPR portion of the DMF-LSPR cartridge may include an LSPR sensor. In other examples, the LSPR portion of the DMF-LSPR cartridge may include an in-line reference channel, wherein the in-line reference channel may be a fluid channel including at least one functionalized LSPR sensor (or sample spot) and at least one non-functionalized LSPR sensor (or reference spot). Additionally, methods of using the PR system for analysis of analytes are provided.

Abstract: A security device that exhibits at least one dynamic response upon change of orientation of the security device with respect to gravity, wherein the security device includes a hollow capsule completely filled with a liquid and one or more microscopic elements. In addition, the dynamic response continues after cessation of the change of orientation with respect to gravity. The dynamic response includes a transition of the one or more microscopic elements from substantial mechanical equilibrium to non-equilibrium upon action of the change of orientation with respect to gravity and back to substantial mechanical equilibrium after cessation of the change of orientation with respect to gravity. During the dynamic response, the one or more microscopic elements undergo at least one of a rotational motion and a translational motion relative to the liquid.

Abstract: A security device that elicits at least one dynamic response upon acceleration, or upon change of orientation with respect to gravity, wherein the dynamic response continues after cessation of the acceleration or the change of orientation. In addition, the dynamic response can be optical, such that it is visually observable by an unaided human eye. Alternatively, the response can be machine readable. In some cases, the dynamic response has duration of from about 0.01 s to about 100 s, or from about Is to about 10 s.

Abstract: A technique for producing an artificial biointerface involves providing a patterned microfluidic chip having: a chamber divided by a fluid-permeable fencing into a central region and two flanking channels; and at least 3 fluid paths, each of the paths extending across one of the central region and the two flanking channels. A porous packing of rigid beads is placed within the central region to define a bead bed, the beads being of a size to be retained by the fencing. A biowall can be grown on at least one segment of the fencing separating the central region from one flanking channel, the biowall formed at least in part by live cells cultured on the beads. Beads may be modified, coated or functionalized to improve cell attachment and growth, and for reporting, or dosing particles or molecules can be conveniently added to the bead bed.

Abstract: A smart ink, comprising microparticles, with each microparticle comprising: a) an exterior shell; b) a liquid encapsulated within the shell; and c) a Janus microparticle suspended in the liquid, wherein the Janus microparticle either comprises: i) two or more distinct assemblies of particles; or ii) a core loaded with particles, the core having a first surface portion and a second surface portion that is functionally distinct from the first surface portion. An apparatus and method for production of the microparticles are also provided.

Abstract: The present application relates to polymer microparticle-metal nanoparticle composites, to methods of preparing polymer microparticle-metal nanoparticle composites and to uses of such composites. The methods comprise introducing into a microfluidic device, a composition comprising: a cationic metal nanoparticle precursor; a polymer microparticle precursor that comprises a plurality of photopolymerizable groups; and a photoreducer-photoinitiator; then irradiating the composition under conditions to simultaneously reduce the cationic metal and polymerize the photopolymerizable groups to obtain the composite.

Abstract: The present application relates to polymer film-metal composites, to methods of preparing polymer film-metal composites and to uses of such composites. The metal can be in the form of a nanoparticle or a film. The methods comprise depositing on a surface, a composition comprising: a cationic metal precursor; a polymer film precursor that comprises a plurality of photopolymerizable groups; and a photoreducer-photoinitiator; then irradiating the composition under conditions to simultaneously reduce the cationic metal and polymerize the photopolymerizable groups to obtain the composite on the surface.

Abstract: Gravitational Janus microparticle having, a center-of-mass, a center-of-volume, and a non¬uniform density, wherein: the center-of-mass and the center-of-volume are distinct. When suspended in a fluid, the microparticle substantially aligns with either: i) the gravitational field; or ii) the direction of an acceleration, such that the Janus microparticle is in substantial rotation equilibrium. After perturbation from substantial rotational equilibrium, the Janus microparticle reversibly rotates to return to substantial rotational equilibrium. The gravitational Janus microparticle may comprise at least two portions, each having distinct physical and/or chemical characteristics, wherein at least one portion provides a detectable effect following rotation and alignment of the microparticle.

Abstract: A security device that elicits at least one dynamic response upon acceleration, or upon change of orientation with respect to gravity, wherein the dynamic response continues after cessation of the acceleration or the change of orientation. In addition, the dynamic response can be optical, such that it is visually observable by an unaided human eye. Alternatively, the response can be machine readable. In some cases, the dynamic response has duration of from about 0.01 s to about 100 s, or from about Is to about 10 s.

Abstract: Gravitational Janus microparticle having, a center-of-mass, a center-of-volume, and a non-uniform density, wherein: the center-of-mass and the center-of-volume are distinct. When suspended in a fluid, the microparticle substantially aligns with either: i) the gravitational field; or ii) the direction of an acceleration, such that the Janus microparticle is in substantial rotation equilibrium. After perturbation from substantial rotational equilibrium, the Janus microparticle reversibly rotates to return to substantial rotational equilibrium. The gravitational Janus microparticle may comprise at least two portions, each having distinct physical and/or chemical characteristics, wherein at least one portion provides a detectable effect following rotation and alignment of the microparticle.

Abstract: A smart ink, comprising microparticles, with each microparticle comprising: a) an exterior shell; b) a liquid encapsulated within the shell; and c) a Janus microparticle suspended in the liquid, wherein the Janus microparticle either comprises: i) two or more distinct assemblies of particles; or ii) a core loaded with particles, the core having a first surface portion and a second surface portion that is functionally distinct from the first surface portion. An apparatus and method for production of the microparticles are also provided.

Abstract: A microfluidic system, particularly suited as a cell culture system, is provided having a single monolithic biocompatible substrate with both a surface having an ordered array of nano-scale elements required for plasmonic response monitoring and a network of microchannels for precisely controlling cellular environment. The system has the additional advantages of low-volume consumption, rapid low-cost fabrication of molds with easily interchangeable microfluidic channel layouts, amenability to mass production, and in situ label-free real-time detection of cellular response, viability, behavior and biomolecular binding using plasmonic techniques. A ratio of greater than 0.2 between the cross-sectional dimension and the spacing distance of the nano-scale elements is useful for plasmonic response monitoring.

Abstract: A microfluidic system has a monolithic biocompatible substrate with both a surface having an ordered array of nano-scale elements for plasmonic response monitoring and a network of microchannels. Advantageously, low-volume consumption, rapid low-cost fabrication of molds with easily interchangeable microfluidic channel layouts, mass production, and in situ label-free real-time detection of cellular response, viability, behavior and biomolecular binding using plasmonic techniques can be provided. A ratio of greater than 0.2 of the cross-sectional dimension and the spacing between the nano-scale elements is useful for plasmonic response monitoring. Producing such a system involves a master mold with the nano-scale elements etched into a hard substrate, and the network provided in a soft membrane bonded to the hard substrate. A stamp may be created by setting a settable liquid polymer or metal placed in the master mold. Features of the intended device can be transferred to a polymeric substrate using the stamp.

Abstract: A microfluidic system, particularly suited as a cell culture system, is provided having a single monolithic biocompatible substrate with both a surface having an ordered array of nano-scale elements required for plasmonic response monitoring and a network of microchannels for precisely controlling cellular environment. The system has the additional advantages of low-volume consumption, rapid low-cost fabrication of molds with easily interchangeable microfluidic channel layouts, amenability to mass production, and in situ label-free real-time detection of cellular response, viability, behavior and biomolecular binding using plasmonic techniques. A ratio of greater than 0.2 between the cross-sectional dimension and the spacing distance of the nano-scale elements is useful for plasmonic response monitoring.