Spontaneous Droplet-Into-Droplet Insertion for Formation of Polymer Particles

The particle sizes are controlled precisely and accurately, and can be varied.Droplet dispensing is very precise.The device can be reconfigured by reprogramming, providing precise control over the rates of droplet generation, movement and insertion, as well as control over the sequence of droplet merging, mixing and reaction agents.Minimal amounts of resources (i.e. surfactants, dispersing liquid are not required) are used, minimizing the chemical waste.The device uses very little power.

Pharmaceutical formulationsLatex paintsHeterogeneous catalystsFabrication of cryogenic targets for inertial confinement fusion energy production

Researchers at UCLA have developed a new microfluidic device to generate spontaneous droplet-to-droplet insertion for formation of polymer particles. This invention utilizes digital microfluidic devices to spontaneously insert one droplet into second droplet in various ambient mediums such as air or an immiscible liquid. This novel microfluidic device can precisely control predetermined, diverse dimensions and shapes of polymer particles or can be used to prepare solid shells containing various materials.

Patent Number: US20120000777A1
Application Number: US13154248A
Inventor: Garrell, Robin L. | Tucker-Schwartz, Alexander K. | Shepherd, Heather | Chatterjee, Debalina
Priority Date: 4 Jun 2010
Priority Number: US20120000777A1
Application Date: 6 Jun 2011
Publication Date: 5 Jan 2012
IPC Current: C25B001500 | B01F000308
US Class: 204451 | 204601
Assignee Applicant: The Regents of the University of California
Title: DEVICES AND METHODS FOR FORMING DOUBLE EMULSION DROPLET COMPOSITIONS AND POLYMER PARTICLES
Usefulness: DEVICES AND METHODS FOR FORMING DOUBLE EMULSION DROPLET COMPOSITIONS AND POLYMER PARTICLES
Summary: The method is useful for forming double emulsion droplets, which are useful for forming a polymer particle (all claimed), and in industrial, research, pharmaceutical contexts, polymer chemistry, food, beverage, health and beauty aids, paints and coatings, and drugs and drug delivery.

Chemical/Material

Chemical/Material Application

20120000777

State Of Development

To date, a digital microfluidic device has been successfully used to actuate a droplet containing monomer and initiator, causing it to insert into a stationary droplet of an immiscible liquid. Their techniques have shown to maintain a spherical inner droplet.

Background

Polymer spheres, spheroids and shells are most commonly made in bulk reactors by suspension or emulsion polymerization requiring additional catalytic or initiating agents, such as salts and surfactants (detergents, emulsifying agents). The monomer can be incorporated into droplets by various methods, most commonly by shaking, stirring, or sonication. The resulting particle size distribution, however, can vary drastically and typically gives a heterogeneous mixture of sizes, especially for larger particles. In addition, the required surfactants and/or emulsifying agents are undesirable as they are difficult to remove completely. 

Recently, fluidics based technology has been developed to generate continuous streams of droplets to form a droplet-in-a-droplet. The dispersed monomeric droplet-in-a-droplets can then polymerize to form polymer disks, spheres, and shells in the sub-micron-to-millimeter diameter size range. Several drawbacks of current fluidic methods include a) uncontrollable droplet size, b) manual and empirical adjustment of the particle size, c) difficult reconfiguration of microfluidic devices, and d) large chemical wastes. 

In addition, the formation of polymer particles by all of the above methods requires the monomer-containing emulsion droplet to be surrounded by another liquid - the dispersing liquid in the case of bulk emulsion or suspension polymerization, or the stripping liquid for tube- and channel-based droplet fluidic system. These liquids result in huge volumes of waste

Related Materials

Additional Technologies by these Inventors

• Synthesis of Thioether Containing Trialkoxysilanes
• Digital Microfluidic Platform for Creating, Maintaining, and Analyzing Cell Spheroids

Tech ID/UC Case

21514/2009-768-0

Related Cases

2009-768-0

USA

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