The present invention relates to the field of microfluidics and in particular to devices and methods for sorting objects in microfluidic channels. These devices and methods allow for fast and robust sorting in two-way and multi-way setups. They also enable sorting over extended periods of time.

Individual biological cells can be selected in a micro-fluidic device and moved into isolation pens in the device. The cells can then be lysed in the pens, releasing nucleic acid material, which can be captured by one or more capture objects in the pens. The capture objects with the captured nucleic acid material can then be removed from the pens. The capture objects can include unique identifiers, allowing each capture object to be correlated to the individual cell from which the nucleic acid material captured by the object originated.

A fluidic apparatus for detection of a chemical substance, a biosensor, and a method of fabricating the fluidic apparatus. The fluidic apparatus includes a fluidic structure arranged to receive a sample containing a target substance, and a trapping structure, in fluid communication with the fluidic structure and arranged to immobilize the target substance in a detection region, wherein the detection region of the trapping structure is arranged to alter a physical characteristic of an incident light signal which represents a concentration of the target substance contained in the sample.

A counting method includes aggregating particles in a sample by the action of first dielectrophoretic force, dispersing the aggregated particles by the action of second dielectrophoretic force, which is different from the first dielectrophoretic force, capturing a dispersion image including the dispersed particles, and determining the number of particles on the basis of the dispersion image.

Methods of selectively positioning a micro-object in a microfluidic device are described in this application. The microfluidic device can comprise an enclosure having an inlet, an outlet, and a flow region connecting the inlet and outlet, and an electrode activation substrate having a photoconductive layer. The methods of selectively positioning can comprising: projecting a first light beam on an electrode activation substrate of the microfluidic device, wherein the first position is proximal to the first micro-object, and wherein the first light beam activates a positive dielectrophoresis (DEP) force within the enclosure sufficient to capture the first micro-object; and projecting a second light beam upon a second position on the electrode activation substrate, wherein the second position is adjacent to or at least partially surrounding the first position, without overlapping the first position, the second light beam activating a positive DEP force within the enclosure sufficient to capture second micro-objects other than the first micro-object. The methods of selectively positioning can further comprise moving the first light beam towards a third position on the electrode activation substrate, wherein the DEP force activated by the first light beam is sufficient to move the first micro-object to the third position. Optionally, the methods can include moving the second light beam in relation to the first light beam to prevent micro-objects other than the first micro-object from being captured by the first light beam. Other embodiments are described.

For some examples, an apparatus to effect particle separation may include a dielectrophoretic particle separator that may separate particles within a focused particle stream. The dielectrophoretic particle separator may apply an electric field to the particles. An imaging system may capture images of the particles passing through a separation region of the dielectrophoretic particle separator. An image processing and control system may process the images to obtain information regarding the particles and may adjust an operating parameter of the dielectrophoretic separator based upon the information regarding the particles.

A microfluidic device can include a base an outer surface of which forms one or more enclosures for containing a fluidic medium. The base can include an array of individually controllable transistor structures each of which can comprise both a lateral transistor and a vertical transistor. The transistor structures can be light activated, and the lateral and vertical transistors can thus be photo transistors. Each transistor structure can be activated to create a temporary electrical connection from a region of the outer surface of the base (and thus fluidic medium in the enclosure) to a common electrical conductor. The temporary electrical connection can induce a localized electrokinetic force generally at the region, which can be sufficiently strong to move a nearby micro-object in the enclosure.

An object separator may include a substrate, a fluid channel supported by the substrate, a pair of electrodes along the fluid channel to form a dielectrophoretic force to interact with an object entrained in a fluid, and an inertial pump supported by the substrate and positioned within the fluid channel to move the fluid along the fluid channel.

The disclosure relates to a dielectrophoretic tweezer, and associated methods of fabrication and use. The tweezer comprises a first end and a second end, in which the first end has a lateral dimension of less than 10 microns; a structure, extending in a longitudinal direction between the first and second ends, comprising an electrically insulating barrier defining a first chamber and a second chamber within the structure, in which the first and second chambers are insulated from each other by the electrically insulating barrier; a first electrode in the first chamber at the first end; and a second electrode in the second chamber at the first end, in which a width of the electrically insulating barrier separating the first electrode from the second electrode is 50 nm or less.

Methods are described herein for isolating clonal populations of T cells having a defined genetic modification. The methods are performed, at least in part, in a microfluidic device comprising one or more sequestration pens. The methods include the steps of: maintaining individual T cells (or precursors thereof) that have undergone a genomic editing process in corresponding sequestration pens of a microfluidic device; expanding the T cells into respective clonal populations of T cells; detecting, in one or more T cells of each clonal population, the absence of a cell surface marker that was present in the individual T cells (or precursors thereof); and detecting, in one or more T cells of each clonal population, the presence of a first nucleic acid sequence that is indicative of the presence of an on-target genome edit in the clonal population of T cells. Also described are compositions comprising one or more clonal populations of T cells isolated according to the methods disclosed herein.