Example methods, apparatus, systems for diluting samples are disclosed. An example method includes depositing a first fluid droplet on a first electrode of a plurality of electrodes. The first electrode has a first area. The first fluid droplet has a first volume associated with the first area. The example method includes depositing a second fluid droplet on a second electrode of the plurality of electrodes. The second electrode has a second area. The second fluid droplet has a second volume associated with the second area. The second volume is different than the first volume. The example method includes forming a combined droplet by selectively activating at least one of the first electrode or the second electrode to cause one of the first fluid droplet or the second fluid droplet to merge with the other of the first fluid droplet or the second fluid droplet.

Provided herein are methods of splitting droplets containing magnetically responsive beads in a droplet actuator. A droplet actuator having a plurality of droplet operations electrodes configured to transport the droplet, and a magnetic field present at the droplet operations electrodes, is provided. The magnetically responsive beads in the droplet are immobilized using the magnetic field and the plurality of droplet operations electrodes are used to split the droplet into first and second droplets while the magnetically responsive beads remain substantially immobilized.

The present application relates to a microfluidic system and its method for use for the separation of motile sperm from immotile sperm or motile bacteria from immotile bacteria. The system includes a housing having a first end, and a second end, with a passage connecting the first and second ends. There is an inlet at the first end of the housing for charging fluids into the passage and an outlet at the second end of said housing for discharging fluids from the passage. There are one or more corrals within the passage, each of the corrals including a closed side and a partially open side. The closed side of the corrals is closer to the first end than the partially open side, with the closed side and partially open side defining between them a confinement region suitable for retaining motile sperm or motile bacteria.

A vacuum manifold for filtration microscopy includes a manifold top having multiple openings, and a capture membrane positioned above and spaced apart from the manifold top, where the capture membrane is configured to deflect into contact with a surface of the manifold top when a negative pressure is applied to the multiple openings. A method for filtration microscopy includes the steps of providing a vacuum manifold including a manifold top having a plurality of openings, and a capture membrane positioned above and spaced apart from the manifold top; applying sample drops to sample spots on the membrane, the sample spots positioned above the plurality of openings; applying a negative pressure to the openings such that the capture membrane contacts a surface of the manifold top; and optically imaging particulates on the capture membrane.

A device for manipulating a droplet comprising water is provided, the device including: (i) a surface configured to support the droplet, the surface including a hydrophobic region; and (ii) an ultrasound transducer array, the ultrasound transducer array being arranged above the surface and separated from the surface; wherein the ultrasound transducer array is configured to emit ultrasound for actuating a motion of the droplet along the surface by subjecting the droplet to an acoustic radiation force by the emitted ultrasound.

Described herein are systems and methods for processing at least one biological sample. The systems and methods may process the biological sample, or plurality thereof, using at least one droplet. The droplet, or plurality thereof, may be manipulated using the systems and methods described herein.

The present invention provides a method for producing dried and stable reagent:substrate complexes suitable for use in various types of assays. Also provided are dried reagent:substrate complexes produced by the method of the invention, as well as methods for their use to perform an assay.

An integrated semiconductor device for manipulating and processing bio-entity samples and methods are described. The device includes a lower substrate, at least one optical signal conduit disposed on the lower substrate, at least one cap bonding pad disposed on the lower substrate, a cap configured to form a capped area, and disposed on the at least one cap bonding pad, a fluidic channel, wherein a first side of the fluidic channel is formed on the lower substrate and a second side of the fluidic channel is formed on the cap, a photosensor array coupled to sensor control circuitry, and logic circuitry coupled to the fluidic control circuitry, and the sensor control circuitry.

A vacuum manifold for filtration microscopy includes a manifold top having multiple openings, and a capture membrane positioned above and spaced apart from the manifold top, where the capture membrane is configured to deflect into contact with a surface of the manifold top when a negative pressure is applied to the multiple openings. A method for filtration microscopy includes the steps of providing a vacuum manifold including a manifold top having a plurality of openings, and a capture membrane positioned above and spaced apart from the manifold top; applying sample drops to sample spots on the membrane, the sample spots positioned above the plurality of openings; applying a negative pressure to the openings such that the capture membrane contacts a surface of the manifold top; and optically imaging particulates on the capture membrane.

A single junction sorter for a microfluidic particle sorter, the single-junction sorter comprising: an input channel, configured to receive a fluid containing particles; an output sort channel and an output waste channel, each connected to the input channel for receiving the fluid therefrom; a bubble generator, operable to selectively displace the fluid around a particle to be sorted and thereby to create a transient flow of the fluid in the input channel; and a vortex element, configured to cause a vortex in the transient flow in order to direct the particle to be sorted into the output sort channel.