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.

A biosensor system includes an array of biosensors with a plurality of electrodes situated proximate the biosensor. A controller is configured to selectively energize the plurality of electrodes to generate a DEP force to selectively position a test sample relative to the array of biosensors.

A microfluidic sorting device and method employing dielectrophoresis (DEP) induced field flow separations are described herein. The microfluidic sorting device has a microchannel and an array of electrodes disposed along the microchannel. The electrodes may be oriented at an angle relative to the microchannel. Non-mammalian samples such as plant samples flow in the microchannel and through the electrode array. Current is passed through the electrodes causing a DEP force to be exerted on the samples. This force may generate a torque that causes one type of sample to rotate and slide along the electrodes, thus separating the samples by type. The separated samples are collected in different output channels

Embodiments for sorting particles are provided that include a microfluidic channel configured to receive a microfluidic flow that comprises a plurality of particles having different characteristics, the microfluidic channel having a plurality of output flow channels, a first detector configured to detect the location of the particles, a plurality of actuators located along the direction of the microfluidic flow and defining a sorting electrode arrangement. The microfluidic device further comprises a controller configured to receive signals from the first detector and to provide force field profiles for each of the plurality of particles, wherein each force field profile comprises a plurality of deflection force settings along the direction of the microfluidic flow. The controller individually addresses the plurality of actuators to generate a plurality of actuation inducing fields along the direction of the microfluidic flow to generate the deflection force settings in the force field profiles.

The microfluidic chip and the microfluidic system of the present invention provides a unique integration of a microfluidic chip and a label-free quantification process. The microfluidic chip uses well arrays and dielectrophoresis (DEP) to capture a polarizable agent in a well. Once the polarizable agents have been captured, non-faradaic electrochemical impedance spectroscopy (nF-EIS) measurements can be performed to quantify the polarizable agent.

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.

A biosensor system includes an array of biosensors with a plurality of electrodes situated proximate the biosensor. A controller is configured to selectively energize the plurality of electrodes to generate a DEP force to selectively position a test sample relative to the array of biosensors.

Methods of sorting T lymphocytes in a microfluidic device are provided. The methods can include flowing a fluid sample comprising T lymphocytes through a region of a microfluidic device that contains an array of posts. The array of posts can be configured to have a critical size (D.sub.c) that separates activated T lymphocytes from naïve T lymphocytes. Also provided are microfluidic devices having an array of posts configured to separate activated T lymphocytes from naïve T lymphocytes, compositions enriched for T lymphocytes, particularly activated T lymphocytes that are known to be reactive to an antigen of interest, and methods of treating subjects suffering from a pathogenic disorder or cancer by administering such compositions.

Methods for fabricating a biochip for detecting or sequencing biomolecules are shown. Such a biochip may for instance include: a base member; a dielectric layer deposited on the base member and having at least two rows of discrete recesses formed thereon; and two or more electrodes sandwiched between the base member and the dielectric layer and running under respective row of discrete recesses, the two or more electrodes separated from each other along lengths thereof by a portion of the dielectric layer; wherein the dielectric layer defines a continuous operation surface above the electrodes and on which the discrete recesses are deposited for detecting or sequencing of biomolecules, when an electric field is applied through the electrodes, a field gradient is created to draw a biomolecule towards a preferred part of the operation surface.