Abstract: A structure for providing a boundary for a chamber in a microfluidic apparatus can comprise dielectrophoresis (DEP) configurations each having an outer surface and electrowetting (EW) configurations each having an electrowetting surface. The DEP configurations can facilitate generating net DEP forces with respect to the outer surfaces of the DEP configurations to move micro-objects on the outer surfaces, and the EW configurations can facilitate changing wetting properties of the electrowetting surfaces to move droplets of liquid medium on the electrowetting surfaces.

Abstract: 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.

Abstract: In some cases, the described systems and methods include obtaining a cell sample containing multiple antibody-producing cells. In such cases, the cells can be tagged with a cross-linking reagent having a first portion configured to bind to a marker on the antibody-producing cells and a second portion configured to bind to an antigen of interest. In some instances, the tagged antibody-producing cells are exposed to the antigen of interest such that the antigen becomes bound to the cells. In some such instances, the antibody-producing cells are also allowed to produce an antibody, such that a portion of the antibody-producing cells produce an antigen-specific antibody that binds to the antigen of interest. To identify cells that produce the antigen-specific antibody, the tagged cells can be exposed to a labeled secondary antibody that is configured to bind to the antigen-specific antibody. Other implementations are also described.

Abstract: A microfluidic optoelectronic tweezers (OET) device can comprise dielectrophoresis (DEP) electrodes that can be activated and deactivated by controlling a beam of light directed onto photosensitive elements that are disposed in locations that are spaced apart from the DEP electrodes. The photosensitive elements can be photodiodes, which can switch the switch mechanisms that connect the DEP electrodes to a power electrode between an off state and an on state.

Abstract: 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.

Abstract: In some cases, the described systems and methods include obtaining a cell sample containing multiple antibody-producing cells. In such cases, the cells can be tagged with a cross-linking reagent having a first portion configured to bind to a marker on the antibody-producing cells and a second portion configured to bind to an antigen of interest. In some instances, the tagged antibody-producing cells are exposed to the antigen of interest such that the antigen becomes bound to the cells. In some such instances, the antibody-producing cells are also allowed to produce an antibody, such that a portion of the antibody-producing cells produce an antigen-specific antibody that binds to the antigen of interest. To identify cells that produce the antigen-specific antibody, the tagged cells can be exposed to a labeled secondary antibody that is configured to bind to the antigen-specific antibody. Other implementations are also described.

Abstract: A micro-fluidic device can include a processing mechanism for processing micro-objects in a liquid medium and an outputting mechanism for expressing from the device a droplet of the medium containing one or more of the micro-objects. The outputting mechanism can include an expressing mechanism having a reservoir for holding a quantity of the liquid medium and a striking mechanism for striking and compressing the expressing mechanism to express a droplet of the medium from the expressing mechanism.