A microfluidic device comprises a lower layer that is electrically conductive and transparent with respect to an incident optical beam, an upper layer, comprising first portions that are electrically conductive and second portions that are electrically insulating, adjacent and alternated to the first ones; a compartment seamlessly extending between the lower layer and the upper layer; the compartment contains a filler medium configured to emit an optical emission beam and markers dispersed in the filler medium, which are electrically charged and are adapted to move inside the compartment in all directions according to the intensity of the electrical signal applied to the first portions, the filler medium is configured to interact with the markers to increase or decrease the intensity of the optical emission beam according to the local concentration of the markers.

Methods for on-demand printing discrete entities including, e.g., cells, media or reagents to substrates are provided. In certain aspects, the methods include manipulating qualities of the entities or biological components thereof. In some embodiments, the methods may be used to create arrays of microenvironments and/or for two and three-dimensional printing of tissues or structures and/or for in situ printing for microsurgeries. Systems and devices for practicing the subject methods are also provided.

Provided herein are systems, methods, and articles of manufacture for collecting and merging two different size droplets using a substrate comprising a plurality of trapping sites. In certain embodiments, provided herein are systems composed of a plurality of larger droplets and smaller droplets and a substrate comprising a plurality of trapping sites where each trapping site is configured to trap only one of the larger droplets and only one of the smaller droplets when the larger droplet is already present at the trapping site. In particular embodiments, the larger and/or smaller droplets are sorted prior to being contacted with the substrate to ensure they contain the desired component (e.g., cell or barcoded bead). In other embodiments, each trapping site is composed of one or multiple fluidically linked capture wells. In some embodiments, collected larger and smaller droplets are merged (e.g., via a demulsifier or electricity).

An apparatus is provided for sensing a molecule in a sample. The apparatus utilizes an electric field to draw molecules from a first chamber through an aperture, defined by a chemical layer, into a second chamber. The apparatus can detect a DNA molecule with, for example, 4, 5, or 6 unique base pairs. As molecules pass through the aperture, a sensor detects or measures a change in an electric parameter used to generate the electric field, thereafter translating the change in the electric parameter into information about the molecule. A divider element separates the first and second chambers and supports a chemical layer defining the aperture. The apparatus enables detection or measurement of molecules over prolonged time at a higher electric field strength than other nanopores, due to a combination of the shape of the divider, structural elements thereon, and thickness of the chemical layer at the aperture.

The present invention generally relates to droplet libraries and to systems and methods for the formation of libraries of droplets. The present invention also relates to methods utilizing these droplet libraries in various biological, chemical, or diagnostic assays.

A microfluidic chip and a fabrication method of the microfluidic chip are provided. The microfluidic chip includes an array substrate, and a hydrophobic layer disposed on a side of the array substrate. The hydrophobic layer includes at least one through-hole, and a through-hole of the at least one through-hole penetrates through the hydrophobic layer along a direction perpendicular to a plane of the array substrate. The microfluidic chip also includes at least one hydrophilic structure. A hydrophilic structure of the at least one hydrophilic structure is disposed in the through-hole.

The present disclosure generally relates to devices for effecting epitachophoresis. Epitachophoresis may be used to effect sample analysis, such as by selective separation, detection, extraction, and/or pre-concentration of target analytes such as, for example, DNA, RNA, and/or other biological molecules. Said target analytes may be collected following epitachophoresis and used for desired downstream applications and further analysis.

A biological chip, a manufacturing method thereof, an operation method thereof, and a biological detection system are provided. The biological chip includes a base substrate and a plurality of working units. The plurality of the working units are arranged on the base substrate; each of the working units includes a working element configured to be in contact with a target substance; and the working element includes a metal electrode and an electric-field-controllable surface modification layer on a surface of the metal electrode.

Methods and systems for sorting particles are provided. Methods and systems for sorting cell beads are provided. In some cases, cell beads may be sorted from particles unoccupied with cell derivatives. In some cases, singularly occupied cell beads may be sorted from unoccupied particles and multiply occupied cell beads.

In one example an apparatus can include a controller communicatively coupled to a droplet dispenser to deposit fluid on a digital microfluidic (DMF) array including a plurality of droplet manipulation electrodes, the controller to: select a first droplet manipulation electrode from the plurality of droplet manipulation electrodes to on which to dispense a first volume of fluid via the droplet dispenser; position the droplet dispenser over the selected first droplet manipulation electrode; and deposit the first volume of fluid onto the selected first droplet manipulation electrode.