Provided herein are methods of splitting droplets containing magnetically responsive beads in a droplet actuator. A droplet actuator having a plurality of droplet operations electrodes configured to transport the droplet, and a magnetic field present at the droplet operations electrodes, is provided. The magnetically responsive beads in the droplet are immobilized using the magnetic field and the plurality of droplet operations electrodes are used to split the droplet into first and second droplets while the magnetically responsive beads remain substantially immobilized.

An integrated semiconductor device for manipulating and processing bio-entity samples and methods are described. The device includes a lower substrate, at least one optical signal conduit disposed on the lower substrate, at least one cap bonding pad disposed on the lower substrate, a cap configured to form a capped area, and disposed on the at least one cap bonding pad, a fluidic channel, wherein a first side of the fluidic channel is formed on the lower substrate and a second side of the fluidic channel is formed on the cap, a photosensor array coupled to sensor control circuitry, and logic circuitry coupled to the fluidic control circuitry, and the sensor control circuitry.

An integrated semiconductor device for manipulating and processing bio-entity samples and methods are described. The device includes a lower substrate, at least one optical signal conduit disposed on the lower substrate, at least one cap bonding pad disposed on the lower substrate, a cap configured to form a capped area, and disposed on the at least one cap bonding pad, a fluidic channel, wherein a first side of the fluidic channel is formed on the lower substrate and a second side of the fluidic channel is formed on the cap, a photosensor array coupled to sensor control circuitry, and logic circuitry coupled to the fluidic control circuitry, and the sensor control circuitry.

The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

The invention describes a method for the synthesis of compounds comprising the steps of: (a) compartmentalising two or more sets of primary compounds into microcapsules; such that a proportion of the microcapsules contains two or more compounds; and (b) forming secondary compounds in the microcapsules by chemical reactions between primary compounds from different sets; wherein one or both of steps (a) and (b) is performed under microfluidic control; preferably electronic microfluidic control The invention further allows for the identification of compounds which bind to a target component of a biochemical system or modulate the activity of the target, and which is co-compartmentalised into the microcapsules.

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.

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.

Various aspects of the present invention relate to the control and manipulation of fluidic species, for example, in microfluidic systems. In one aspect, the invention relates to systems and methods for making droplets of fluid surrounded by a liquid, using, for example, electric fields, mechanical alterations, the addition of an intervening fluid, etc. In some cases, the droplets may each have a substantially uniform number of entities therein. For example, 95% or more of the droplets may each contain the same number of entities of a particular species. In another aspect, the invention relates to systems and methods for dividing a fluidic droplet into two droplets, for example, through charge and/or dipole interactions with an electric field. The invention also relates to systems and methods for fusing droplets according to another aspect of the invention, for example, through charge and/or dipole interactions. In some cases, the fusion of the droplets may initiate or determine a reaction. In a related aspect of the invention, systems and methods for allowing fluid mixing within droplets to occur are also provided. In still another aspect, the invention relates to systems and methods for sorting droplets, e.g., by causing droplets to move to certain regions within a fluidic system. Examples include using electrical interactions (e.g., charges, dipoles, etc.) or mechanical systems (e.g., fluid displacement) to sort the droplets. In some cases, the fluidic droplets can be sorted at relatively high rates, e.g., at about 10 droplets per second or more. Another aspect of the invention provides the ability to determine droplets, or a component thereof, for example, using fluorescence and/or other optical techniques (e.g., microscopy), or electric sensing techniques such as dielectric sensing.