Devices, systems, and methods for generating droplets

A method of producing droplets comprising a non-biological particle, the method comprising:

• (a) providing a device comprising a first channel having an outlet and comprising a first liquid comprising non-biological particles and a reservoir comprising a second liquid having an interface with a fluid;
• and
• (b) transporting the first liquid through the outlet and causing relative motion of the outlet and the interface to produce droplets of the first liquid and the non-biological particle in the second liquid.

A system for producing droplets of a first liquid in a second liquid, the system comprising a device comprising a first channel having an outlet and a reservoir comprising a second liquid having an interface with a fluid;

• wherein the system is configured to cause relative motion of the outlet with respect to the interface so that the outlet crosses the interface;
• and
• wherein the reservoir comprises a shunt configured to maintain a substantially constant vertical location of the interface as droplets are formed.

A system for producing droplets of a first liquid in a second liquid, the system comprising a device comprising a first channel having an outlet, a reservoir comprising a second liquid having an interface with a fluid, and an actuator operatively coupled to the second liquid to move the interface relative to the outlet;

• wherein the system is configured to cause relative motion of the outlet with respect to the interface so that the outlet crosses the interface.

A device for producing droplets, comprising:

• i) a first channel having a first proximal end and a first distal end, wherein the first distal end is open to the exterior of the device;
• and
• ii) a second channel having a second proximal end and a second distal end, wherein the first and second channels intersect between the first proximal and first distal ends.

A method of collecting droplets comprising:

• a) providing a device comprising a trough having an inlet and an outlet and comprising a second liquid;
• b) allowing droplets of a first liquid to enter the trough as the second liquid flows from the inlet to the outlet, wherein the first and second liquids are immiscible with each other.

A method of collecting droplets comprising:

• a) providing a moving plate comprising a second liquid;
• and
• b) allowing droplets of a first liquid to contact the second liquid as the plate moves, wherein the droplets are transported away from the point of contact and the first and second liquids are immiscible with each other.

A method of collecting droplets comprising:

• a) providing a reservoir comprising a second liquid that partially fills the reservoir;
• and
• b) allowing droplets of a first liquid to contact the second liquid as the second liquid is moved, wherein the droplets move therefrom, and the first and second liquids are immiscible with each other.

A system for producing droplets or decreasing the size of droplets, the system comprising a device comprising a first channel having an inlet and an outlet and a source of electromagnetic energy disposed to illuminate liquid or droplets exiting the outlet.