Various embodiments comprise systems, methods, architectures, mechanisms or apparatus configured to separate particles of varying size within a fluid flow, or filter particles from a fluid flow, via an array of anchored-liquid drops or anchored-gas drops.

A device for manipulating microdroplets using optically-mediated electrowetting comprising: a first composite wall comprising: a first transparent substrate; a first transparent conductor layer on the substrate having a thickness of 70 to 250 nm; a photoactive layer activated by electromagnetic radiation in the wavelength range 400-1000 nm on the conductor layer having a thickness of 300-1000 nm; and a first dielectric layer on the conductor layer having a thickness of 120-160 nm; a second composite wall comprised of: a second substrate; a second conductor layer on the substrate having a thickness of 70 to 250 nm; and an A/C source to provide a voltage across the first and second composite walls connecting the first and second conductor layers; at least one source of electromagnetic radiation having an energy higher than the bandgap of the photoexcitable layer; and means for manipulating the points of impingement of the electromagnetic radiation on the photoactive layer.

The present disclosure provides a reaction cassette for biochemical test. The reaction cassette includes a structural wall, a first flow guiding member and an obstacle member. The structural wall defines a reaction region and a channel region, wherein the reaction region is connected to the channel region. The first flow guiding member is disposed in the channel region, and a first angle between the structural wall and the first flow guiding member ranges between 0 and 60 degrees. The obstacle member is disposed on the structural wall, and a second angle between the obstacle member and the structural wall is greater than 90 degrees. The present disclosure further provides an assay device including said reaction assay for biochemical test.

Microfluidic probe head for processing a sequence of separate liquid volumes separated by spacers. The microfluidic probe head includes: an inlet, an outlet, a first fluid channel and a second fluid channel and a fluid bypass connecting the first fluid channel and the second fluid channel. The first fluid channel delivers the sequence of separate liquid volumes from the inlet toward a deposition area, the fluid bypass allows the spacers to be removed from the first fluid channel obtaining a free sequence of separate liquid volumes without spacers, the first fluid channel delivers the free sequence of separate liquid volumes to the deposition area, and the second fluid channel delivers the removed spacers from the fluid bypass to the outlet. The present invention also provides a microfluidic probe and method for processing a sequence of separate liquid volumes.

Methods and apparatus for driving flow in a microfluidic arrangement are provided. In one disclosed arrangement, the microfluidic arrangement comprises a first liquid held predominantly by surface tension in a shape defining a microfluidic pattern on a surface of a substrate. The microfluidic pattern comprises at least an elongate conduit and a first reservoir. The area of contact between the substrate and a portion of the first liquid that forms the elongate conduit defines a conduit footprint. The area of contact between the substrate and a portion of the first liquid that forms the first reservoir defines a first reservoir footprint. The size and shape of each of the conduit footprint and the first reservoir footprint are such that a maximum Laplace pressure supportable by the first liquid in the elongate conduit without any change in the conduit footprint is higher than a maximum Laplace pressure supportable by the first liquid in the first reservoir without any change in the first reservoir footprint. A delivery member having an internal lumen leading to a distal opening through which liquid can be delivered is provided. Liquid is pumped into the microfluidic pattern through the distal opening while the distal opening is held in a delivery position. The delivery position is such that the liquid enters the microfluidic pattern via the elongate conduit and drives a flow of liquid into the first reservoir.

In one aspect, single-sided microfluidic devices are described herein. In some embodiments, a single-sided microfluidic device comprises a substrate, a photoconductive layer positioned over the substrate, electrical contacts in electrical communication with the photoconductive layer, and a dielectric assembly positioned over the photoconductive layer. The dielectric assembly comprises a hydrophobic surface for receiving a liquid. In some embodiments, the dielectric assembly has an effective capacitance of about 10 F/m.sup.2 to about 10,000 F/m.sup.2 and/or an average thickness between about 20 nm and about 2000 nm.

Methods are provided for separating magnetically responsive beads from a droplet in a droplet actuator. Droplet operations electrodes and a magnet are arranged in a droplet actuator to manipulate a bead-containing droplet and position it relative to a magnetic field region that attracts the magnetically responsive beads. The droplet operations electrodes are operated to control the droplet shape and transport it away from the magnetic field region to form a concentration of beads in the droplet. The continued transport of the droplet away from the magnetic field causes the concentration of beads to break away from the droplet to yield a small, concentrated bead-containing droplet immobilized by the magnet.

Apparatus for processing life-based organic particles, including particles selected from the list comprising cells, cellular spheroids, tissues, eukaryotes, micro-organisms, organs or embryos, comprises a hollow volume (10) that (a) is internally divided into at least first (14), second (16) and third (17) sub-volumes by at least two phaseguides (12, 13) formed inside the volume and (b) includes parts that are relatively upstream and relatively downstream when judged with reference to the movement of a meniscus or a bulk liquid in the volume (10). The apparatus includes at least first, second and third fluid conduits (19, 21, 22) connected to permit fluid communication between the upstream exterior of the volume (10) and a respective said sub-volume (14, 16, 17); and at least one further conduit (24) connected to permit fluid communication between the downstream exterior of the volume (10) and a said sub-volume. The first sub-volume (14) contains one or more life-based particles supported in or by a gel or gel-like substance; and the second sub-volume (16) communicates with the first sub-volume so as to permit transport of substances between the first and second sub-volumes (14, 16) and contains at least one gel or gel-like substance.

Example paper substrate diagnostic apparatus and related methods and systems are disclosed herein. An example substrate-based diagnostic device includes a hydrophobic substrate, an electrode disposed on a surface of the hydrophobic substrate, a layer of reagent disposed on or near the electrode, and a layer of hydrophilic ink disposed over the electrode and the layer of reagent. The hydrophilic ink is to wick a sample to the layer of reagent.

A microfluidic probe head for providing a sequence of separate liquid volumes separated by spacers, the separate liquid volumes including a respective target substance associated with a respective target area, the microfluidic probe head including an inlet and an outlet; a first fluid channel fluidly connected to the inlet, the first fluid channel configured for delivering an injection liquid from the inlet to a respective target area; a second fluid channel fluidly connected to the outlet, the second fluid channel configured for delivering liquid volumes from the respective target area to the outlet; and a spacer insertion unit fluidly connected to the second fluid channel, the spacer insertion unit configured for inserting spacers into the second fluid channel between the liquid volumes to provide the sequence of separate liquid volumes separated by spacers.