Versitech, Inc.

The University of Hong Kong

Harvard College

Ho Cheung Shum

Yang Song

Alban Sauret

Zhou Liu

Zida Li

David A Weitz

Liang-Yin Chu

Enric Santanach Carreras

Alberto Fernandez-Nieves

Liqiu Wang

Andrew S Utada

Wing Fu Lai

Qingming Ma

Lang Nan

Tiantian Kong

Yuk Heng Tang

An automatic system which combines a three-branch sorter with three independently-controlled valves and corresponding collection platforms. The subgroups of droplets are alternatively sorted into three channels followed by being pumped out into PCR tubes on the platforms. Experimentally, this system can realize an accurate collection with a large working range for both pure positive samples and mixed samples with negative ones. This technology effectively dispenses a large number of droplets into small subgroups with quantitative number, which builds the basis for digital droplet microfluidics.

Automatic microfluidic system for continuous and quantitive collection of droplets

Methods for preparing capsules, such as micro- and/or nanocapsules from all-aqueous emulsions are described herein. The method includes mixing, combining, or contacting a first electrically charged phase containing a first solute with at least an optionally charged second phase containing a second solute. The solutes are incompatible with each other. The electrostatic forces between the two solutions induce the formation of droplets of a dispersed phase in a continuous phase. The droplets are then solidified to form the capsules.

Core-shell capsules for encapsulation of particles, colloids, and cells

A method and apparatus for generating droplets with a high level of uniformity in liquid systems that present a low interfacial tension. This method and apparatus utilize the breakup of the dispersed phase in a controlled fashion by periodically varying the pressure that drives the fluids so as to successfully generate emulsions with a good control over the size. The method and apparatus can be used for the formation of simple emulsion or double emulsion where a larger droplet contains one or more smaller droplets.

System and method for generation of emulsions with low interfacial tension and measuring frequency vibrations in the system

A method and apparatus are provided for mixing highly viscous fluids to form a mixture. The mixture is created rapidly and has a high level of uniformity. The mixture is created by utilizing induced viscous fluid folding under the influence of an electric field. The electric field is introduced by connecting a nozzle dispensing the fluids in parallel to a voltage supply and grounding a collection plate located below the nozzle. When a certain voltage is applied the co-flow viscous fluids start to fold because the electric field exerts stress on the surface of the fluids, which results in changes of the geometry and dynamics of the viscous fluids. Control of the electric field provides great control over the mixture.

Method and apparatus for rapid mixing of highly viscous fluids

Described herein is a drug delivery system, which is based on a novel polymer namely hypromellose-graft-chitosan (HC), useful to deliver a drug to a patient in sustained and controlled release fashion. HC is highly water soluble across the pH range from 1.2 to 10, and has a high pH buffering capacity to provide a pH-stable environment for drug delivery. In addition, the drug delivery system provided herein exhibited a drug loading efficiency of over 90% in all drugs tested, which is 1-2 fold higher than the efficiency attainable by conventional chitosan, and achieved a 2-3 fold longer duration of sustained drug release.

Hypromellose-graft-chitosan and methods thereof for sustained drug delivery

Methods for preparing all-aqueous emulsions, including stable emulsions or emulsions having high viscosity and/or ultra-low interfacial tension are described. The method includes mixing, combining, or contacting a first electrically charged phase containing a first solute (e.g., dispersed phase) with at least a second phase containing a second solute (e.g., continuous phase). The solutes are incompatible with each other. The electrostatic forces between the two phases induce the formation of droplets of a dispersed phase in a continuous phase. The dispersed and continuous phases contain oppositely charged molecules, such as surfactants or other macromolecules and colloids which stabilize the drops of the dispersed phase. Complex coacervation of the oppositely charged molecules or colloids at the interface of the two aqueous phases results in formation of a membrane or barrier which prevents coalescence or aggregation of the droplets. The membrane also prevents leakage of any encapsulated agents from the droplets.

Stabilized all-aqueous emulsions and methods of making and using thereof

A one-step method for fabricating solidified particles from all-aqueous emulsion droplets involves solidification and drying of the droplets by osmosis. According to this method the fabrication of solidified particles is induced by implementing a high osmotic pressure gradient between the internal phase and external phase of the all-aqueous emulsion. The resultant extraction of water leads to solidification of the emulsion droplets. This approach provides mild conditions for encapsulating bioactive ingredients or other delicate components to conveniently fabricate bio- and cyto-compatible particles because it does not involve the introduction of external energy used in conventional drying. Such conventional external energy inputs are time-consuming, so the method is more efficient.

Osmotic drying of all-aqueous emulsions

The present invention generally relates to emulsions such as multiple emulsions, and to methods and apparatuses for making emulsions, and techniques for using the same. A multiple emulsion generally describes larger droplets that contain one or more smaller droplets therein which, in some cases, can contain even smaller droplets therein, etc. Emulsions, including multiple emulsions can be formed in certain embodiments with generally precise repeatability, and can be tailored to include any number of inner droplets, in any desired nesting arrangement, within a single outer droplet. In addition, in some aspects of the invention, one or more droplets may be controllably released from a surrounding droplet.

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Hong Kong, China

Ho Cheung Shum