A fluid manifold includes an inlet comprising an opening into an interior of the fluid manifold, an outlet end that is positioned opposite the inlet and that is in fluid communication with the inlet, a shroud extending between the inlet and the outlet end and surrounding a flow path of the fluid manifold, and a first flow distributor positioned within the interior of the fluid manifold. The first flow distributor includes a hollow body including a first surface at a downstream side of the first flow distributor and a second surface at an upstream side of the first flow distributor, a central cavity defined by the second surface of the hollow body, and openings extending from the first surface to the second surface such that a fluid can pass from the central cavity through the openings. The first flow distributor and the fluid manifold are integrally formed.

Microfluidic devices are provided for conducting fluid assays, for example biological assays, that have the ability to move fluids through multiple channels and pathways in a compact, efficient, and low cost manner. Discrete flow detection elements, preferably extremely short hollow flow elements, with length preferably less than 700 micron, preferably less than 500 micron, and internal diameter preferably of between about 50+/25 micron, are provided with capture agent, and are inserted into microfluidic channels by tweezer or vacuum pick-and-place motions at fixed positions in which they are efficiently exposed to fluids for conducting assays. Close-field electrostatic attraction is employed to define the position of the elements and enable ready withdrawal of the placing instruments. The microfluidic devices feature flow elements, channels, valves, and on-board pumps that are low cost to fabricate accurately, are minimally invasive to the fluid path and when implemented for the purpose, can produce multiplex assays on a single portable assay cartridge (chip) that have low coefficients of variation. Novel methods of construction, assembly and use of these features are presented, including co-valent bonding of selected regions of faces of surface-activatable bondable materials, such as PDMS to PDMS and PDMS to glass, while contiguous portions of one flexible sheet completes and seals flow channels, fixes the position of inserted analyte-detection elements in the channels, especially short hollow flow elements through which sample and reagent flow, and other portions form flexible valve membranes and diaphragms of pumps. A repeated make-and-break-contact manufacturing protocol prevents such bonding to interfere with moving the integral valve diaphragm portions from their valve seats defined by the opposed sheet member, which the flexible sheet material engages. Preparation of two subassemblies, each having a backing of relatively rigid material, followed by their assembly face-to-face in a permanent bond is shown. Hollow detection flow elements are shown fixed in channels, that provide by-pass flow paths of at least 50% of the flow capacity through the elements; in preferred implementations, as much as 100% or more. Metallized polyester film is shown to have numerous configurations and advantages in non-permanently bonded constructions. A method of preparing detection elements for an assay comprises batch coating detection elements, or hollow flow elements by mixing and picking and placing the elements in flow channels of a microfluidic device, capturing the flow elements by bonding two opposed layers while sealing the flow channels.

A fluidic device comprises a first channel conduit, a valve apparatus, and an additional element adjacent to the first channel conduit. The first channel conduit transports fluid from a first fluid entrance to a fluid exit. In one embodiment, the additional element is a pump chamber that receives fluid from a second fluid entrance and pumps fluid into the first channel conduit in accordance with fluid pressure. Alternatively, the additional elements include a second channel conduit and a neck of the first channel conduit. The first channel conduit and the second channel conduit share a common wall. Fluid pressure in the first channel conduit controls a valve apparatus. The value apparatus controls a rate of fluid flow in the first channel conduit by deforming the common wall to change a cross-sectional area of the neck, which changes a rate of fluid flow in the second channel conduit.

A fluidic device comprises a first channel conduit, a valve apparatus, and an additional element adjacent to the first channel conduit. The first channel conduit transports fluid from a first fluid entrance to a fluid exit. In one embodiment, the additional element is a pump chamber that receives fluid from a second fluid entrance and pumps fluid into the first channel conduit in accordance with fluid pressure. Alternatively, the additional elements include a second channel conduit and a neck of the first channel conduit. The first channel conduit and the second channel conduit share a common wall. Fluid pressure in the first channel conduit controls a valve apparatus. The value apparatus controls a rate of fluid flow in the first channel conduit by deforming the common wall to change a cross-sectional area of the neck, which changes a rate of fluid flow in the second channel conduit.

A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

The present disclosure describes a new type of selective nitrophobic surface membrane in a plasma actuator that separates oxygen from nitrogen in the atmosphere, thereby increasing the presence of oxygen near an exposed electrode of the plasma actuator. Accordingly, the plasma flow created in the presence of oxygen at the exposed electrode generates more force than plasma flow created in the presence of nitrogen.

A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.