A microfluidic device can comprise at least one swept region that is fluidically connected to unswept regions. The fluidic connections between the swept region and the unswept regions can enable diffusion but substantially no flow of media between the swept region and the unswept regions. The capability of biological micro-objects to produce an analyte of interest can be assayed in such a microfluidic device. Biological micro-objects in sample material loaded into a microfluidic device can be selected for particular characteristics and disposed into unswept regions. The sample material can then be flowed out of the swept region and an assay material flowed into the swept region. Flows of medium in the swept region do not substantially affect the biological micro-objects in the unswept regions, but any analyte of interest produced by a biological micro-object can diffuse from an unswept region into the swept region, where the analyte can react with the assay material to produce a localized detectable reaction. Any such detected reactions can be analyzed to determine which, if any, of the biological micro-objects are producers of the analyte of interest.

A device for sorting bio-particles by image-manipulated electric force includes a first substrate, a second substrate, a fluidic channel, one or more photosensitive layers and an inlet hole. The first substrate has a first conductive electrode, and the second substrate has a second conductive electrode. The second conductive electrode is disposed opposite the first conductive electrode. The fluidic channel is disposed between the first conductive electrode and the second conductive electrode. The photosensitive layer is conformally disposed on at least one of the surfaces of the first conductive electrode and the second conductive electrode. The inlet hole is disposed in the first conductive electrode and the first substrate, where the inlet hole includes a first opening close to the fluidic channel and a second opening away from the fluidic channel, and the surface area of the first opening is greater than the surface area of the second opening.

A method for stretching a plurality of sample isolates, including: trapping the plurality of sample isolates away from a wall of at least one microfluidic channel of a microfluidic flow system; generating a microfluidic flow to stretch the plurality of trapped sample isolates; determining deformation characteristics of the plurality of stretched samples isolates based on one or more frames from an image processing system; and outputting information corresponding to the deformation characteristics.

A system for orienting particles in a microfluidic system includes one or more radiation pressure sources arranged to expose particles to radiation pressure to cause the particles to adopt a particular orientation in the fluid. A system for sorting particles in a microfluidic system includes a detection stage arranged to detect at least one difference or discriminate between particles in the fluid flow past the detection stage, and one or more radiation pressure sources past which the particles move sequentially and a controller arranged to switch radiation energy to cause a change in direction of movement of selected particles in the fluid flow to sort the particles. The particles may be biological particles such as spermatazoa. The radiation pressure may be optical pressure and may be from one or more waveguides which may extend across a channel of the microfluidic system.

The combined value of integrating optical forces and electrokinetics allows for the pooled separation vectors of each to be applied, providing for separation based on combinations of features such as size, shape, refractive index, charge, charge distribution, charge mobility, permittivity, and deformability. The interplay of these separation vectors allow for the selective manipulation of analytes with a finer degree of variation. Embodiments include methods of method of separating particles in a microfluidic channel using a device comprising a microfluidic channel, a source of laser light focused by an optic into the microfluidic channel, and a source of electrical field operationally connected to the microfluidic channel via electrodes so that the laser light and the electrical field to act jointly on the particles in the microfluidic channel. Other devices and methods are disclosed.

Characteristics of polarizable particles in a fluid are detected using an optical cavity comprising opposed optical reflectors containing the fluid. A particle is introduced through the fluid into the optical cavity. The particle may be transiently in the cavity or optically trapped. The optical cavity containing the particle is illuminated with light that excites resonance of an optical mode of the optical cavity that is affected by the particle. A measurement of a parameter of the excited resonance is derived, for example while tuning through the resonance. Repeated measurements may be used to derive a measure of a characteristic of the particle that is dependent on the motion of the particle in the optical cavity.

Individual biological micro-objects can be deterministically selected and moved into holding pens in a micro-fluidic device. A flow of a first liquid medium can be provided to the pens. Physical pens can be structured to impede a direct flow of the first medium into a second medium in the pens while allowing diffusive mixing of the first medium and the second medium. Virtual pens can allow a common flow of medium to multiple ones of the pens.

Optically-actuated microfluidic devices permit the use of spatially-modulated light to manipulate micro-objects such as biological cells. Systems and methods are described for providing sequences of light patterns to move and direct a plurality of micro-objects within the environment of a microfluidic device. The sequenced light patterns provide improved efficiency in directing the transport of the plurality of micro-objects. Other embodiments are described.

The present invention provides microfabricated substrates and methods of conducting reactions within these substrates. The reactions occur in plugs transported in the flow of a carrier-fluid.

A microfluidic device can comprise at least one swept region that is fluidically connected to unswept regions. The fluidic connections between the swept region and the unswept regions can enable diffusion but substantially no flow of media between the swept region and the unswept regions. The capability of biological micro-objects to produce an analyte of interest can be assayed in such a microfluidic device. Biological micro-objects in sample material loaded into a microfluidic device can be selected for particular characteristics and disposed into unswept regions. The sample material can then be flowed out of the swept region and an assay material flowed into the swept region. Flows of medium in the swept region do not substantially affect the biological micro-objects in the unswept regions, but any analyte of interest produced by a biological micro-object can diffuse from an unswept region into the swept region, where the analyte can react with the assay material to produce a localized detectable reaction. Any such detected reactions can be analyzed to determine which, if any, of the biological micro-objects are producers of the analyte of interest.