Abstract: MicroElectroMechanical System (MEMS) devices can be fabricated completely of hydrogel materials. Such hydrogels can include polyethylene glycol with diacrylate functional groups (e.g., PEGDA), which are photopolymerizable in the presence of crosslinkers and photoinitiators. By using PEGDA monomers of different molecular weights and at different percentages, the mechanical properties of the polymerized gels and their respective permeabilities can be tuned. This spatial variation in properties and permeabilities can lead to different functionalities between different portions of the hydrogel MEMS device. Portions of the hydrogel device may be remotely actuated by applying wave energy, for example, a magnetic field, high intensity focused ultrasound, and/or infrared radiation. The remote actuation can allow the device to be actuated in vivo, for example, to allow the device to deliver a drug or other substance at a desired time and/or desired location within a patient.

Abstract: An extracellular matrix (ECM)-based scaffold suitable for artificial skin as well as other structures can be formed using a bioreactor fabricated with a pattern that introduces desired structural features, on the microscale and/or nanoscale, to ECM-precursors gelled in the bioreactor. The bioreactor can produce a finely patterned scaffold—over clinically relevant size scales—sufficiently robust for routine handling. Preformed ECM-based scaffolds can also have microscale and/or nano-scale structural features introduced into a surface thereof. ECM-based scaffolds may be formed with well-defined structural features via microetching and/or remodeling via ‘contact degradation.’ A surface-activated pattern can be used to degrade the ECM-based scaffold at contact regions between the pattern and the ECM. The produced ECM-based scaffolds can have structures of dimensions conducive to host tissue ingrowth while preserving the fibrous structure and ligand density of natural ECMs.

Abstract: An assay method is described, which comprises the steps of immobilizing a binding partner (e.g., an antigen or antibody) for an analyte to be detected (e.g., an antibody or antigen) on a portion of a surface of a microfluidic chamber; passing a fluid sample over the surface and allowing the analyte to bind to the binding partner; allowing a metal colloid, e.g., a gold-conjugated antibody, to associate with the bound analyte; flowing a metal solution, e.g., a silver solution, over the surface such as to form an opaque metallic layer; and detecting the presence of said metallic layer, e.g., by visual inspection or by measuring light transmission through the layer, conductivity or resistance of the layer, or metal concentration in the metal solution after flowing the metal solution over the surface.

Abstract: The present invention relates generally to microfluidic structures, and more specifically, to microfluidic structures and methods including meandering and wide channels. Microfluidic systems can provide an advantageous environment for performing various reactions and analysis due to a reduction in sample and reagent quantities that are required, a reduction in the size of the operating system, and a decrease in reaction time compared to conventional systems. Unfortunately, the small size of microfluidic channels can sometimes result in difficulty in detecting a species without magnifying optics (such as a microscope or a photomultiplier). A series of tightly packed microchannels, i.e., a meandering region, or a wide channel having a dimension on the order of millimeters, can serve as a solution to this problem by creating a wide measurement area.

Abstract: Fluidic connectors, methods, and devices for performing analyses (e.g., immunoassays) in microfluidic systems are provided. In some embodiments, a fluidic connector having a fluid path is used to connect two independent channels formed in a substrate so as to allow fluid communication between the two independent channels. One or both of the independent channels may be pre-filled with reagents (e.g., antibody solutions, washing buffers and amplification reagents), which can be used to perform the analysis. These reagents may be stored in the channels of the substrate for long periods amounts of time (e.g., 1 year) prior to use.

Abstract: A particle counter for analyzing blood has features which provide for automatic operation and preferably, also provide for portable use in a low resource setting. In a preferred embodiment, preferred embodiment, the device is used to obtain CD4 counts for AIDS diagnosis.

Abstract: Microfabricated platforms can be used to study a heterogeneous panel of biosamples in a realistic in vivo setting. The platform can be formed of a polymer (e.g., a hydrogel) and can be constructed for implantation into an animal host for in vivo testing. The platform can have a plurality of testing regions therein that are constructed to allow exposure of the testing region to the host stroma when implanted in vivo. For example, the microfabricated platform can be used for screening different cancer cell-lines (e.g., to identify which cell line responds to an anti-cancer drug) or for screening different biomaterials (e.g., to identify a composition with ideal host response for a specific implantable device).

Abstract: Fluidic connectors, methods, and devices for performing analysis (e.g., immunoassays) in microfluidic systems are provided. In some embodiments, a fluidic connector having a fluid path is used to connect two independent channels formed in a substrate so as to allow fluid communication between the two independent channels. One or both of the independent channels may be pre-filled with reagents (e.g., antibody solutions, washing buffers and amplification reagents), which can be used to perform the analysis. These reagents may be stored in the channels of the substrate for long periods amounts of time (e.g., 1 year) prior to use.

Abstract: A method and apparatus for delivering one or more fluids. Fluids may be delivered sequentially from a common vessel to a chemical, biological or biochemical process.

Abstract: Microfabricated microvalves may be used with liquid-filled control channels and actuated using compact and battery-powered components, without the need for heavier or fixed infrastructure. The disclosed embodiments include microvalves with on-off fluid control with relatively fast response times, coordinated switching of multiple valves, and operation of a biological (enzyme-substrate) assay in a handheld configuration.

Abstract: MicroElectroMechanical System (MEMS) devices can be fabricated completely of hydrogel materials. Such hydrogels can include polyethylene glycol with diacrylate functional groups (e.g., PEGDA), which are photopolymerizable in the presence of crosslinkers and photoinitiators. By using PEGDA monomers of different molecular weights and at different percentages, the mechanical properties of the polymerized gels and their respective permeabilities can be tuned. This spatial variation in properties and permeabilities can lead to different functionalities between different portions of the hydrogel MEMS device. Portions of the hydrogel device may be remotely actuated by applying wave energy, for example, a magnetic field, high intensity focused ultrasound, and/or infrared radiation. The remote actuation can allow the device to be actuated in vivo, for example, to allow the device to deliver a drug or other substance at a desired time and/or desired location within a patient.

Abstract: Fluidic connectors, methods, and devices for performing analyses (e.g., immunoassays) in microfluidic systems are provided. In some embodiments, a fluidic connector having a fluid path is used to connect two independent channels formed in a substrate so as to allow fluid communication between the two independent channels. One or both of the independent channels may be pre-filled with reagents (e.g., antibody solutions, washing buffers and amplification reagents), which can be used to perform the analysis. These reagents may be stored in the channels of the substrate for long periods amounts of time (e.g., 1 year) prior to use.

Abstract: Fluidic connectors, methods, and devices for performing analyses (e.g., immunoassays) in microfluidic systems are provided. In some embodiments, a fluidic connector having a fluid path is used to connect two independent channels formed in a substrate so as to allow fluid communication between the two independent channels. One or both of the independent channels may be pre-filled with reagents (e.g., antibody solutions, washing buffers and amplification reagents), which can be used to perform the analysis. These reagents may be stored in the channels of the substrate for long periods amounts of time (e.g., 1 year) prior to use.

Abstract: Fluidic connectors, methods, and devices for performing analyses (e.g., immunoassays) in microfluidic systems are provided. In some embodiments, a fluidic connector having a fluid path is used to connect two independent channels formed in a substrate so as to allow fluid communication between the two independent channels. One or both of the independent channels may be pre-filled with reagents (e.g., antibody solutions, washing buffers and amplification reagents), which can be used to perform the analysis. These reagents may be stored in the channels of the substrate for long periods amounts of time (e.g., 1 year) prior to use. Prior to connection of the fluid connector and the substrate, the fluid path may be filled with a sample (e.g., blood). The sample may be obtained, for example, by pricking a finger of a user until blood is drawn from the finger into the fluid path (e.g., by capillary forces).

Abstract: A method and apparatus for delivering one or more fluids. Fluids may be delivered sequentially from a common vessel to a chemical, biological or biochemical process.

Abstract: A particle counter for analyzing blood has features which provide for automatic operation and preferably, also provide for portable use in a low resource setting. In a preferred embodiment, preferred embodiment, the device is used to obtain CD4 counts for AIDS diagnosis.

Abstract: Method and device for storing and/or delivering fluids, wherein at least a first and a second fluid, such as chemical or biochemical reagents or rinse solutions, are maintained separately from each other in a common vessel and transferred in series from the vessel to a reaction site to carry out a predetermined chemical or biochemical reaction. Separation may be achieved by interposing a third fluid, e.g., a gaseous fluid plug, between the first and second fluids.

Abstract: A chemiluminescence-based detection system and method for counting blood cells by capturing and isolating target blood cells flowing through a microfluidic chip and detecting light emitted by the captured target blood cells.

Abstract: An extracellular matrix (ECM)-based scaffold suitable for artificial skin as well as other structures can be formed using a bioreactor fabricated with a pattern that introduces desired structural features, on the microscale and/or nanoscale, to ECM-precursors gelled in the bioreactor. The bioreactor can produce a finely patterned scaffold—over clinically relevant size scales—sufficiently robust for routine handling. Preformed ECM-based scaffolds can also have microscale and/or nano-scale structural features introduced into a surface thereof. ECM-based scaffolds may be formed with well-defined structural features via microetching and/or remodeling via ‘contact degradation.’ A surface-activated pattern can be used to degrade the ECM-based scaffold at contact regions between the pattern and the ECM. The produced ECM-based scaffolds can have structures of dimensions conducive to host tissue ingrowth while preserving the fibrous structure and ligand density of natural ECMs.

Abstract: An assay method is described, which comprises the steps of immobilizing a binding partner (e.g., an antigen or antibody) for an analyte to be detected (e.g., an antibody or antigen) on a portion of a surface of a microfluidic chamber; passing a fluid sample over the surface and allowing the analyte to bind to the binding partner; allowing a metal colloid, e.g., a gold-conjugated antibody, to associate with the bound analyte; flowing a metal solution, e.g., a silver solution, over the surface such as to form an opaque metallic layer; and detecting the presence of said metallic layer, e.g., by visual inspection or by measuring light transmission through the layer, conductivity or resistance of the layer, or metal concentration in the metal solution after flowing the metal solution over the surface.