Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: The ability to levitate, to separate, and to detect changes in density using diamagnetic particles suspended in solutions containing paramagnetic cations using an inhomogeneous magnetic field is described. The major advantages of this separation device are that: i) it is a simple apparatus that does not require electric power (a set of permanent magnets and gravity are sufficient for the diamagnetic separation and collection system to work); ii) it is compatible with simple optical detection (provided that transparent materials are used to fabricate the containers/channels where separation occurs; iii) it is simple to collect the separated particles for further processing; iv) it does not require magnetic labeling of the particles/materials; and v) it is small, portable.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: Paper-based microfluidic systems and methods of making the same are described.

Abstract: We disclose methods and compositions for preparation of stimuli-responsive plastics that are capable of responding to chemical and/or physical signals in their environment. In one embodiment the plastics consist of patterned mixtures of poly(phthalaldehyde) polymers in which each polymer contains a different end-capping group (also called a “trigger”), responsive to a different signal. Other embodiments use different polymers and different triggers. The plastics may be homogeneous in composition, but each polymer within the plastic is capable of responding to a different signal and depolymerizing once this signal reacts with the trigger. This process of depolymerization enables the plastic to alter its physical features non-linearly to external signals: i.e., the degree of change in physical form is much larger than the intensity of the initial signal.

Abstract: The disclosure provides low cost, portable three-dimensional devices for performing multiplexed assays. The devices comprise at least two substantially planar layers disposed in parallel planes, wherein one of the layers is movable relative to each other parallel to the planes to permit the establishment of fluid flow communication serially between the two layers.

Abstract: We disclose methods and compositions for preparation of stimuli-responsive plastics that are capable of responding to chemical and/or physical signals in their environment. In one embodiment the plastics consist of patterned mixtures of poly(phthalaldehyde) polymers in which each polymer contains a different end-capping group (also called a “trigger”), responsive to a different signal. Other embodiments use different polymers and different triggers. The plastics may be homogeneous in composition, but each polymer within the plastic is capable of responding to a different signal and depolymerizing once this signal reacts with the trigger. This process of depolymerization enables the plastic to alter its physical features non-linearly to external signals: i.e., the degree of change in physical form is much larger than the intensity of the initial signal.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: Three-dimensional microfluidic devices including by a plurality of patterned porous, hydrophilic layers and a fluid-impermeable layer disposed between every two adjacent patterned porous, hydrophilic layers are described. Each patterned porous, hydrophilic layer has a fluid-impermeable barrier which substantially permeates the thickness of the porous, hydrophilic layer and defines boundaries of one or more hydrophilic regions within the patterned porous, hydrophilic layer. The fluid-impermeable layer has openings which are aligned with at least part of the hydrophilic region within at least one adjacent patterned porous, hydrophilic layer. Microfluidic assay device, microfluidic mixer, microfluidic flow control device are also described.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.

Abstract: The disclosure provides low cost, portable three-dimensional devices for performing multiplexed assays. The devices comprise at least two substantially planar layers disposed in parallel planes, wherein one of the layers is movable relative to each other parallel to the planes to permit the establishment of fluid flow communication serially between the two layers.

Abstract: A fluidic device having a first layer with a first layer wicking channel and a second layer extending across the first layer and having a second layer functional wicking channel. The fluidic device can further include a third layer extending across the second layer, the third layer having a third layer functional wicking channel. The second layer functional wicking channel can have a different function than the third layer functional wicking channel and the functional wicking channels can afford for the fluidic device to be used as a timer, a battery, and/or a chemical assay.

Abstract: Three-dimensional microfluidic devices including by a plurality of patterned porous, hydrophilic layers and a fluid-impermeable layer disposed between every two adjacent patterned porous, hydrophilic layers are described. Each patterned porous, hydrophilic layer has a fluid-impermeable barrier which substantially permeates the thickness of the porous, hydrophilic layer and defines boundaries of one or more hydrophilic regions within the patterned porous, hydrophilic layer. The fluid-impermeable layer has openings which are aligned with at least part of the hydrophilic region within at least one adjacent patterned porous, hydrophilic layer. Microfluidic assay device, microfluidic mixer, microfluidic flow control device are also described.

Abstract: Paper-based microfluidic systems and methods of making the same are described.

Abstract: The ability to levitate, to separate, and to detect changes in density using diamagnetic particles suspended in solutions containing paramagnetic cations using an inhomogeneous magnetic field is described. The major advantages of this separation device are that: i) it is a simple apparatus that does not require electric power (a set of permanent magnets and gravity are sufficient for the diamagnetic separation and collection system to work); ii) it is compatible with simple optical detection (provided that transparent materials are used to fabricate the containers/channels where separation occurs; iii) it is simple to collect the separated particles for further processing; iv) it does not require magnetic labeling of the particles/materials; and v) it is small, portable.

Abstract: Embodiments of the invention provide lateral flow and flow-through bioassay devices based on patterned porous media, methods of making same, and methods of using same. Under one aspect, an assay device includes a porous, hydrophilic medium; a fluid impervious barrier comprising polymerized photoresist, the barrier substantially permeating the thickness of the porous, hydrophilic medium and defining a boundary of an assay region within the porous, hydrophilic medium; and an assay reagent in the assay region.