This application provides fluidic devices, such as microfluidic devices, which can be used for the creation and/or manipulation of droplets in droplet-based microfluidic systems, as well as systems and methods for using the same. The microfluidic devices can be used to generate droplets, extract or inject volume to droplets, and/or split droplets. Also provided are methods for generating nucleosomes, and isolated DNA from nucleosomes (or from non-nucleosomes), for example using the disclosed devices.

Devices, systems, and their methods of use, for generating droplets are provided. One or more geometric parameters of a microfluidic channel can be selected to generate droplets of a desired and predictable droplet size.

A method for aliquoting a sample liquid using a sealing liquid in a microfluidic device includes combining the sample liquid and the sealing liquid, which have different wetting behaviors, to form a two-phase system separated by a boundary surface. The microfluidic device includes a chamber with at least one inlet channel for introducing the liquids and a plurality of cavities configured to be filled via the inlet channel. The inlet channel and the cavities have a geometry that is defined in dependence on the respective wetting behaviors of the sample liquid and the sealing liquid. The method first includes introducing the sample liquid to form a first meniscus configured by the defined geometry, e.g. concave, to fill the cavities. The method further includes introducing the sealing liquid to form a second meniscus configured by the existing, greater contact angle and the defined geometry, e.g. convex, to cover the filled cavities.

The present invention generally relates to systems and methods to create stable emulsions with low rates of exchange of molecules between microdroplets.

The invention provides sample cartridges for processing samples. The sample cartridges comprise at least one fluidic channel. Each fluidic channel comprises a sample chamber, a lysis chamber, a binding chamber, a pre-amplification region, and an amplification region. The sample cartridges also comprise a waste line that is in fluidic connectivity with each fluidic channel. The sample cartridges can interface with a plurality of plungers that are capable of occluding at least one fluidic channel, waste line, and/or optional assay line to limit the transport of fluids into, out of, and/or along at least one fluidic channel by plunging. The invention also provides multi-channel sample cartridges, which are sample cartridges that comprise at least two fluidic channels. In addition, the sample cartridges can house fluids on the cartridge, off the cartridge, or some on the cartridge and some fluids off the cartridge.

A method of encapsulating a solid sample in a droplet, the method including flowing a continuous phase through a first fluid channel at a first flow rate; flowing a dispersed phase through a second fluid channel at a second flow rate, the dispersed phase including a plurality of particles, cells or beads; trapping the plurality of particles, cells or beads in a mixing region that receives the dispersed phase and the continuous phase; and reducing the first flow rate to encapsulate the trapped particles, cells or beads in droplets of the dispersed phase generated when the dispersed phase and the continuous phase exit the mixing region through an orifice.

A point of use analyzer includes pump, valve, port, and storage channel. The storage channel may hold multiple assay packets composed of reagent aliquots separated by bounding slugs. The storage channel may define an elongated lumen having two ends with each of the ends coupled to the valve. A sampling device for use with the analyzer engages the port and may include a recurrent coaxial tube having a separation medium. A method of using the analyzer with the sampling device includes steps of pumping a fluid to displace a sample into the separation medium and out through the opposed connection.

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).

This relates to acoustic microfluidic systems that can generate emulsions/droplets or encapsulate particles of interest (including mammalian cells, bacteria cells, or other cells) into droplets upon detection of the particles of interest flowing in a stream of particles. The systems operate on the detect/decide/deflect principle wherein the deflection step, in a single operation, not only deflects particles of interest from a stream of particles but also encapsulates the particles of interest in an emulsion droplet. The microfluidic systems have an abrupt transition in the channel geometry from a shorter channel to a taller channel (i.e., in the shape of a ‘step’) to break the stream of the dispersed phase into a droplet upon acoustic actuation. When there is no acoustic wave present, no droplets/emulsions are generated and the stream of particles proceeds uninterrupted. The rapid actuation and post-actuation recovery employed by the microfluidic systems taught herein ensure that the vast majority of selected particles are properly deflected, that few or no empty droplets are produced, and that total throughput remains high.

The present disclosure provides a microfluidic chip and a droplet separation method, and belongs to the field of biological chip technology. The microfluidic chip includes a first liquid tank and a second liquid tank opposite to each other and a channel layer therebetween. The channel layer includes a plurality of microfluidic channels separated from each other, first ends of the microfluidic channels are communicated with the first liquid tank, and second ends are communicated with the second liquid tank. The first liquid tank contains sample solution to be detected, and the second liquid tank contains encapsulating liquid. The sample solution to be detected entering the first liquid tank may be separated into a plurality of sample droplets through the microfluidic channels, the separated sample droplets enter the second liquid tank, so that the encapsulating liquid is encapsulated on a surface of each of the plurality of sample droplets.