Provided is a method of mixing first and second liquids having mutual solubility inside a mixing flow channel formed by a micro flow channel. This method includes: causing the first and second liquids to be joined to each other inside the mixing flow channel; and forming a slug flow, in which mixing subject cells (60) formed by the joined liquid and insoluble fluid cells (63) formed by an insoluble fluid are alternately arranged, inside a flow channel at the downstream side of an insoluble fluid supply position in a manner such that the insoluble fluid having insolubility with respect to both mixing subject liquids is supplied to the joined liquid flowing through the flow channel in a direction intersecting the flow channel so that the joined liquid is divided with a gap therebetween, thereby mixing the first mixing subject liquid and the second mixing subject liquid contained in each mixing subject cell inside the downstream flow channel.

Methods, devices and systems for handling sample liquids, encapsulating liquids and magnetic particles are disclosed.

The present invention generally relates to the manipulation of fluids using acoustic waves such as surface acoustic waves. In some aspects, one fluid may be introduced into another fluid via application of suitable acoustic waves. For example, a fluid may be added or injected into another fluid by applying acoustic waves where, in the absence of the acoustic waves, the fluid cannot be added or injected, e.g., due to the interface or surface tension between the fluids. Thus, for example, a fluid may be injected into a droplet of another fluid. Other embodiments of the invention are generally directed to systems and methods for making or using such systems, kits involving such systems, or the like.

A droplet actuator for manipulating a fluid using an electrical field includes a droplet arranged on or over an electrode. The droplet includes a set of beads arranged substantially in a monolayer on or over a surface of the droplet actuator.

Disclosed herein are systems and methods for serial flow emulsion processes. Systems and methods as described herein can result in reduced cross-contamination, greater accuracy and precision, less expensive materials and processes, decreased run times, and/or other advantages, e.g., through use of improved injectors, partitioners, detectors, and/or other elements useful in serial flow emulsion systems and processes.

The invention provides methods for assessing one or more predetermined characteristics or properties of a microfluidic droplet within a microfluidic channel, and regulating one or more fluid flow rates within that channel to selectively alter the predetermined microdroplet characteristic or property using a feedback control.

A method of preparing a Metal Organic Framework (MOF) with an acoustically-driven microfluidic platform, the method comprising: depositing a liquid comprising MOF precursors on a piezoelectric substrate of an acoustic microfluidic platform, the MOF precursors comprising a metal ion and an organic ligand, applying acoustic irradiation to the liquid to induce azimuthal liquid recirculation, which causes formation of the MOF within the liquid, and isolating the MOF.

Methods of concentrating beads in a droplet and/or loading beads on a fluidic device are provided, including among other things, a method of concentrating beads in a droplet, the method comprising: (a) providing a droplet actuator comprising: (i) an interior droplet operations volume; and (ii) a reservoir exterior to the interior volume; (iii) a droplet established in a liquid path extending from the reservoir into the interior volume; (b) providing magnetically responsive beads in the portion of the droplet which is in the reservoir; (c) magnetically attracting the magnetically responsive beads through the liquid path into the portion of the droplet which is in the interior volume; and (d) forming a droplet comprising one or more of the magnetically responsive beads in the interior volume.

The present invention generally relates to systems and methods for the control of fluids and, in some cases, to systems and methods for flowing a fluid into and/or out of other fluids. As examples, fluid may be injected into a droplet contained within a fluidic channel, or a fluid may be injected into a fluidic channel to create a droplet. In some embodiments, electrodes may be used to apply an electric field to one or more fluidic channels, e.g., proximate an intersection of at least two fluidic channels. For instance, a first fluid may be urged into and/or out of a second fluid, facilitated by the electric field. The electric field, in some cases, may disrupt an interface between a first fluid and at least one other fluid. Properties such as the volume, flow rate, etc. of a first fluid being urged into and/or out of a second fluid can be controlled by controlling various properties of the fluid and/or a fluidic droplet, for example curvature of the fluidic droplet, and/or controlling the applied electric field.

A control method and related apparatus are disclosed for controlling actuation voltages applied to array elements of an element array on an electrowetting on dielectric (EWOD) device, wherein test metrics are determined and employed for optimizing subsequent droplet manipulation operations. The control method includes the steps of: receiving a liquid droplet onto the element array; applying an electrowetting actuation pattern of actuation voltages to actuate the droplet to modify a footprint of the droplet from a first state having an initial footprint to a second state having a modified footprint; sensing the modified footprint with a sensor; determining a test metric from sensing the modified footprint indicative of one or more droplet properties based on a droplet response of the liquid droplet to the electrowetting actuation pattern; and controlling actuation voltages applied to the array elements based on the test metric. The test metrics may include a transition rate and/or conformance to an actuation pattern.