A device for automatically and selectively dispensing multiple additives into a base liquid is disclosed, where each additive is dispensed by a control mechanism that effectively shuts off and is self-cleaning. In one embodiment, each additive is provided through a channel comprising a tube, a check disk, and a fulcrum. When the pressure of a particular additive increases above a threshold, a flexure is created in the check disk, which causes an opening that allows the additive to enter a main channel where it is mixed with a base liquid. When the pressure of the liquid additive is decreased below the threshold, the check disk reverts to its original form and the additive is no longer dispensed into the base liquid. Thereafter, the base liquid cleanses the mechanism.

A method of dispensing a graded material includes generating droplets of a first working material, the droplets having a size in the range of 10 nanometers to 10 micrometers, adding the droplets of the first working material into a carrier fluid to create a first emulsion, wherein addition of the droplets of the first working material is controlled to create gradient in the emulsion, mixing the first emulsion to create a homogenous, graded mixture, and dispensing the homogenous, graded mixture onto a surface.

The invention provides kits, devices, methods, and systems for forming droplets or particles and methods of their use. The devices may be used to form droplets of a size suitable for utilization as microscale chemical reactors, e.g., for genetic sequencing. In general, droplets are formed in a device by flowing a first liquid through a channel and into a droplet formation region including a second liquid, i.e., the continuous phase. The invention allows for more efficient recovery of droplets or processed droplets.

A dissolution generator apparatus includes: a dissolution generator, including: a housing shell; a powder support screen assembly extending across an interior of the housing shell and configured to support a column of powder; a pressure mechanism disposed adjacent the powder support screen assembly; a spray delivery assembly located adjacent the powder support screen assembly opposite to the pressure mechanism, the spray delivery assembly comprising a spray nozzle configured to spray a solvent through the powder support screen assembly; a duct having a first end in fluid communication with the housing shell, and a second end; a dissolved powder reservoir in fluid communication with the second end of the duct; and at least one recirculation pump disposed in fluid communication with both the dissolved powder reservoir and the spray delivery assembly, so as to form a fluid recirculation loop between the dissolved powder reservoir and the spray delivery assembly.

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.

The present invention generally relates to the production of fluidic droplets. Certain aspects of the invention are generally directed to systems and methods for creating droplets by flowing a fluid from a first channel to a second channel through a plurality of side channels. The fluid exiting the side channels into the second channel may form a plurality of droplets, and in some embodiments, at very high droplet production rates. In addition, in some aspects, double or higher-order multiple emulsions may also be formed. In some embodiments, this may be achieved by forming multiple emulsions through a direct, synchronized production method and/or through the formation of a single emulsion that is collected and re-injected into a second microfluidic device to form double emulsions.

A mixing system has a parallel droplet dispenser capable of making droplets of a first working material in the range of 10 nanometers to 10 micrometers, a pump to deliver fluid for the droplets of the first working material and to produce a first emulsion, a compact mixer having low inter-voxel mixing to receive the emulsion and produce a homogenous material, and a dispensing system. A method of dispensing a graded material includes generating droplets of a first working material, the droplets having a size in the range of 10 nanometers to 10 micrometers, adding the droplets of the first working material into a fluid to create a first emulsion, wherein addition of the droplets of the first working material is controlled to create gradient in the emulsion, mixing the first emulsion to create a homogenous, graded mixture, and dispensing the homogenous, graded mixture onto a surface.

The present disclosure is directed to cross-flow membrane emulsification devices. The devices disclosed herein can have a continuous phase plate, a dispersed phase plate, an outlet, and a chamber. The chamber is located between the continuous phase plate and the dispersed phase plate and is bisected by a membrane with a plurality of pores. The chamber can include at least one channel on a first side of the membrane formed from at least one groove in the continuous phase plate and the membrane. In addition, the chamber can also include a cavity on a second side of the membrane formed in the dispersed phase plate.

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 microfluidic apparatus includes a substrate defining a microchannel having inlet and an outlet defining a length of the microchannel. The microchannel has a main channel extending from the inlet to the outlet, and a plurality of side cavities extending from the main channel. The cavities are in fluid communication with the main channel. A method includes introducing a sample into the microchannel through the inlet to fill the entire microchannel, and then introducing a solvent into the microchannel through the inlet at a controlled flow rate and inlet pressure. A developed solvent front then moves along the main channel from the inlet to the outlet while displacing the sample in the main channel. Images of the microchannel are acquired as the front moves, and a miscibility condition is determined based on the images.