Patents by Inventor David A. Weitz

David A. Weitz has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20160279068
    Abstract: The invention relates to microparticles comprising a crosslinked gel and methods for making and using same.
    Type: Application
    Filed: November 4, 2014
    Publication date: September 29, 2016
    Inventors: Stefanie Utech, Radivoje Prodanovic, Esther Amstad, Raluca Ostafe, David A. Weitz, Angelo S. Mao, David J. Mooney, Connie Chang Wilking, Wang Huanan
  • Publication number: 20160271513
    Abstract: The present invention generally relates to microfluidics, and to spray drying and other drying techniques. Various embodiments of the invention are generally directed to systems and methods for drying fluids contained within a channel such as a microfluidic channel. For example, a fluid may be partially or completely dried within a microfluidic channel, prior to being sprayed into a collection region. In some embodiments, the fluids may be dried relatively rapidly, resulting in spray-dried particles that are partially or completely amorphous. For instance, the fluid may contain salts, drugs, small molecules, ceramics, inorganic species, metals, sugars, polymers, etc., which may be dried to form partially or completely amorphous nanoparticles containing these species.
    Type: Application
    Filed: October 29, 2014
    Publication date: September 22, 2016
    Inventors: David A. Weitz, Esther Amstad, Frans Spaepen
  • Publication number: 20160250638
    Abstract: Articles and methods for controlling flow in fluidic systems, especially in microfluidic systems, are provided. In one aspect, a microfluidic system described herein includes a configuration such that the actuation of a single valve can allow the switching of fluids from a first fluid path (e.g., a first channel section) to a second fluid path (e.g., a second channel section). This may be achieved, for example, by incorporating a valve with a first channel section, which may have a lower hydrodynamic resistance than a second channel section prior to actuation of the valve. Actuation of the valve can cause only the hydrodynamic resistance of the first channel section to increase, thereby redirecting fluid flow into the second channel section (which now has a relatively lower hydrodynamic resistance).
    Type: Application
    Filed: May 6, 2016
    Publication date: September 1, 2016
    Applicant: President and Fellows of Harvard College
    Inventors: Adam R. Abate, David A. Weitz
  • Publication number: 20160201129
    Abstract: The present invention generally relates to fluidic droplets, and to techniques for screening or sorting such fluidic droplets. In some embodiments, the fluidic droplets may contain cells such as immune cells, which can be analyzed to determine receptor sequences or other useful properties of the cells. For example, in one aspect, the present invention is generally related to determining immune cell receptors by encapsulating immune cells and target cells in microfluidic droplets, determining the effect of the immune cells on the target cells, and for those immune cells that kill or otherwise adversely affect the target cells, determining one or more receptor sequences of those immune cells. The target cells may be, for example, cancer cells or virally-infected cells. In some cases, the receptor sequences can be used, for example, to identify certain properties of the immune cells, to screen for drugs or other therapeutic agents, or the like.
    Type: Application
    Filed: August 22, 2014
    Publication date: July 14, 2016
    Applicant: President and Fellows of Harvard College
    Inventors: David A. Weitz, John Heyman, John R. Gilbert
  • Publication number: 20160193574
    Abstract: The present invention generally relates to emulsions, and more particularly, to double and other multiple emulsions. Certain aspects of the present invention are generally directed to the creation of double emulsions and other multiple emulsions at a common junction of microfluidic channels. In some cases, the microfluidic channels at the common junction may have substantially the same hydrophobicity. In one set of embodiments, a device may include a common junction of six or more channels, where a first fluid flows through one channel, a second fluid flows through two channels, and a third or carrying fluid flows through two more channels, such that a double emulsion of a first droplet of the first fluid, contained in a second droplet of the second fluid, contained by the carrying fluid, flows away from the common junction through a sixth channel.
    Type: Application
    Filed: December 7, 2015
    Publication date: July 7, 2016
    Inventors: David A. Weitz, Assaf Rotem, Adam R. Abate, Christian Holtze
  • Publication number: 20160186256
    Abstract: The invention describes a method for isolating one or more genetic elements encoding a gene product having a desired activity, comprising the steps of: (a) compartmentalising genetic elements into microcapsules; and (b) sorting the genetic elements which express the gene product having the desired activity; wherein at least one step is under microfluidic control. The invention enables the in vitro evolution of nucleic acids and proteins by repeated mutagenesis and iterative applications of the method of the invention.
    Type: Application
    Filed: February 1, 2016
    Publication date: June 30, 2016
    Inventors: Andrew David Griffiths, David A. Weitz, Darren R. Link, Keunho Ahn, Jerome Bibette
  • Publication number: 20160168386
    Abstract: A structurally colored pigment is described that contains a plurality of photonic crystal particles dispersed in a medium, where each photonic crystal particles contains a plurality of spectrally selective absorbing components dispersed within the photonic crystal particle. In certain embodiments, each photonic crystal particle has a predetermined minimum number of repeat units of the photonic crystal structure. The structurally colored material provides improved reflectance, long-term stability, and control of the desired optical effects. The fabrication techniques described herein also provide high throughput and high yield allowing use in wide ranging applications from cosmetics, paints, signs, sensors, to packaging material.
    Type: Application
    Filed: July 13, 2014
    Publication date: June 16, 2016
    Applicant: President and Fellows of Harvard College
    Inventors: Joanna AIZENBERG, Nicolas VOGEL, Ian BURGESS, Mathias KOLLE, Tanya SHIRMAN, Stefanie UTECH, Katherine PHILLIPS, David A. WEITZ, Natalie KOAY
  • Patent number: 9358539
    Abstract: Articles and methods for controlling flow in fluidic Systems, especially in microfluidic Systems, are provided. A microfluidic System includes a configuration such that the actuation of a single valve can allow the switching of fluids from a first fluid path (e.g., a first channel section) to a second fluid path (e.g., a second channel section). This may be achieved by incorporating a valve (38) with a first channel section (24), which may have a lower hydrodynamic resistance than a second channel section (28) prior to actuation of the valve. Actuation of the valve (38) can cause only the hydrodynamic resistance of the first channel section (24) to increase, thereby redirecting fluid flow into the second channel section (28) (which now has a relatively lower hydrodynamic resistance). The valve comprises a control channel (40) for introducing a positive or reduced pressure, and is adapted to modulate fluid flow in an adjacent channel section by constricting or expanding the channel section (24).
    Type: Grant
    Filed: May 15, 2009
    Date of Patent: June 7, 2016
    Assignee: President and Fellows of Harvard College
    Inventors: Adam R. Abate, David A. Weitz
  • Publication number: 20160144329
    Abstract: The present invention generally relates to microparticles and, in particular, to systems and methods for encapsulation within microparticles. In one aspect, the present invention is generally directed to microparticles containing entities therein, where the entities contain an agent that can be released from the microparticles, e.g., via diffusion. In some cases, the agent may be released from the microparticles without disruption of the microparticles. The entities may be, for instance, polymeric particles, hydrogel particles, droplets of fluid, etc. The entities may be contained within a fluid that is, in turn, encapsulated within the microparticle. The agent may be released from the entity into the fluid, and then from the fluid through the microparticle. In such fashion, the release of agent from the microparticle may be controlled, e.g., over relatively long time scales.
    Type: Application
    Filed: November 19, 2015
    Publication date: May 26, 2016
    Inventors: John Christopher Wesner, Marco Caggioni, Taotao Zhu, David A Weitz, Alireza Abbaspourrad, Chang-Hyung Choi
  • Publication number: 20160145535
    Abstract: The present invention generally relates to microparticles and, in particular, to systems and methods for encapsulation within microparticles. In one aspect, the present invention is generally directed to microparticles containing entities therein, where the entities contain an agent that can be released from the microparticles, e.g., via diffusion. In some cases, the agent may be released from the microparticles without disruption of the microparticles. The entities may be, for instance, polymeric particles, hydrogel particles, droplets of fluid, etc. The entities may be contained within a fluid that is, in turn, encapsulated within the microparticle. The agent may be released from the entity into the fluid, and then from the fluid through the microparticle. In such fashion, the release of agent from the microparticle may be controlled, e.g., over relatively long time scales.
    Type: Application
    Filed: November 19, 2015
    Publication date: May 26, 2016
    Inventors: John Christopher Wesner, Marco Caggioni, Taotao Zhu, David A. Weitz, Alireza Abbaspourrad, Chang-Hyung Choi
  • Publication number: 20160144330
    Abstract: The present invention generally relates to microparticles and, in particular, to systems and methods for encapsulation within microparticles. In one aspect, the present invention is generally directed to microparticles containing entities therein, where the entities contain an agent that can be released from the microparticles, e.g., via diffusion. In some cases, the agent may be released from the microparticles without disruption of the microparticles. The entities may be, for instance, polymeric particles, hydrogel particles, droplets of fluid, etc. The entities may be contained within a fluid that is, in turn, encapsulated within the microparticle. The agent may be released from the entity into the fluid, and then from the fluid through the microparticle. In such fashion, the release of agent from the microparticle may be controlled, e.g., over relatively long time scales.
    Type: Application
    Filed: November 19, 2015
    Publication date: May 26, 2016
    Inventors: John Christopher Wesner, Marco Caggioni, Taotao Zhu, David A. Weitz, Alireza Abbaspourrad, Chang-Hyung Choi
  • Publication number: 20160129444
    Abstract: The present invention generally relates to microfiuidics, and, in particular, to systems and methods for coalescing or fusing droplets. In certain aspects, two or more droplets within a microfluidic channel are brought together and caused to coalesce without using electric fields or charges. For example, in certain embodiments, droplets stabilized with a surfactant may be disrupted, e.g., by exposing the droplets to a solvent able to alter the surfactant, which may partially destabilize the droplets and allow them to coalesce. In some instances, the droplets may also be physically disrupted to facilitate coalesce. In addition, in some cases, the positions of one or more droplets may be controlled within a channel using a groove in a wall of the channel. For example, a droplet may at least partially enter the groove such that the position of the droplet is at least partially controlled by the groove.
    Type: Application
    Filed: June 12, 2014
    Publication date: May 12, 2016
    Applicant: President and Fellows of Harvard College
    Inventors: David A. Weitz, Thomas E. Kodger, Donald Aubrecht, Ilke Akartuna
  • Publication number: 20160091145
    Abstract: 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.
    Type: Application
    Filed: May 14, 2014
    Publication date: March 31, 2016
    Applicant: President and Fellows of Harvard College
    Inventors: David A. Weitz, Esther Amstad
  • Publication number: 20160023126
    Abstract: The present invention generally relates to microfluidics, and to spray drying and other drying techniques. In some aspects, an article containing one or more channels or microfluidic channels is used to mix one or more fluids prior to spray drying. The mixing may occur immediately before the fluids are expelled through a nozzle or other opening into a drying region of the spray dryer. In one set of embodiments, for example, a first fluid is exposed to a second fluid, then the fluids are exposed to air or other gases before being expelled through a nozzle. In certain instances, the first fluid may contain a dissolved species that may precipitate upon exposure to the second fluid; such precipitation may occur immediately before expulsion through a nozzle or other opening, thereby resulting in controlled precipitation as part of the spray drying process.
    Type: Application
    Filed: August 25, 2015
    Publication date: January 28, 2016
    Applicants: President and Fellows of Harvard College, BASF SE
    Inventors: Adam R. Abate, Julian W.P. Thiele, David A. Weitz, Christian Holtze, Maike Windbergs
  • Patent number: 9238206
    Abstract: The present invention generally relates to emulsions, and more particularly, to double and other multiple emulsions. Certain aspects of the present invention are generally directed to the creation of double emulsions and other multiple emulsions at a common junction of microfluidic channels. In some cases, the microfluidic channels at the common junction may have substantially the same hydrophobicity. In one set of embodiments, a device may include a common junction of six or more channels, where a first fluid flows through one channel, a second fluid flows through two channels, and a third or carrying fluid flows through two more channels, such that a double emulsion of a first droplet of the first fluid, contained in a second droplet of the second fluid, contained by the carrying fluid, flows away from the common junction through a sixth channel.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: January 19, 2016
    Assignees: President and Fellows of Harvard College, BASF SE
    Inventors: Assaf Rotem, David A. Weitz, Adam R. Abate, Christian Holtze
  • Publication number: 20160008778
    Abstract: Devices and methods for dividing droplets are generally described. In some embodiments, an article may comprise a fluidic channel comprising an array of obstructions. In certain embodiments, the arrangement of obstructions in the array may affect the flow path of fluid in the channel. For example, the array of obstructions may be used to convert a polydisperse population of droplets into a relatively monodisperse population of droplets. Passing a polydisperse population of droplets through the array may result in the division of droplets such that the population of droplets exiting the array has a narrower distribution in the characteristic dimensions of the droplets. The arrangement of obstructions in the array may allow for high-throughput production of a substantially monodisperse population of droplets in some cases. In some embodiments, the population of droplets exiting the array may be converted into particles.
    Type: Application
    Filed: March 5, 2014
    Publication date: January 14, 2016
    Inventors: David A. Weitz, Esther Amstad, Ralph Alexander Sperling
  • Publication number: 20160000886
    Abstract: The present invention provides nano structured active therapeutic vehicles which include a biodegradable polymeric fiber and/or thread comprising a porous particle which encapsulates an active agent. The vehicles of the present invention may be used to provide sustained release of the active agent to a subject.
    Type: Application
    Filed: February 21, 2014
    Publication date: January 7, 2016
    Inventors: Kevin Kit Parker, Johan Ulrik Lind, David A. Weitz, Nichlaus J. Carroll, Alireza Abbaspourrad
  • Publication number: 20150360186
    Abstract: Parallel uses of microfluidic methods and devices for focusing and/or forming discontinuous sections of similar or dissimilar size in a fluid are described. In some aspects, the present invention relates generally to flow-focusing-type technology, and also to microfluidics, and more particularly parallel use of microfluidic systems arranged to control a dispersed phase within a dispersant, and the size, and size distribution, of a dispersed phase in a multi-phase fluid system, and systems for delivery of fluid components to multiple such devices.
    Type: Application
    Filed: May 12, 2015
    Publication date: December 17, 2015
    Inventors: Mark Romanowsky, Adam R. Abate, David A. Weitz
  • Publication number: 20150353999
    Abstract: The present invention generally relates to droplets and/or emulsions, such as multiple emulsions. In some cases, the droplets and/or emulsions may be used in assays, and in certain embodiments, the droplet or emulsion may be hardened to form a gel. In some aspects, a heterogeneous assay can be performed using a gel. For example, a droplet may be hardened to form a gel, where the droplet contains a cell, DNA, or other suitable species. The gel may be exposed to a reactant, and the reactant may interact with the gel and/or with the cell, DNA, etc., in some fashion. For example, the reactant may diffuse through the gel, or the hardened particle may liquefy to form a liquid state, allowing the reactant to interact with the cell. As a specific example, DNA contained within a gel particle may be subjected to PCR (polymerase chain reaction) amplification, e.g., by using PCR primers able to bind to the gel as it forms. As the DNA is amplified using PCR, some of the DNA will be bound to the gel via the PCR primer.
    Type: Application
    Filed: May 26, 2015
    Publication date: December 10, 2015
    Inventors: Jeremy Agresti, Liang-Yin Chu, David A. Weitz, Jin-Woong Kim, Amy Rowat, Morten Sommer, Gautam Dantas, George Church
  • Publication number: 20150336072
    Abstract: The present invention is generally related to systems and methods for producing a plurality of droplets. The droplets may contain varying species, e.g., for use as a library. In some cases, the fluidic droplets may be rigidified to form rigidified droplets (e.g., gel droplets). In certain embodiments, the droplets may undergo a phase change (e.g., from rigidified droplets to fluidized droplets), as discussed more herein. In some cases, a species may be added internally to a droplet by exposing the droplet to a fluid comprising a plurality of species.
    Type: Application
    Filed: July 29, 2015
    Publication date: November 26, 2015
    Inventors: David A. Weitz, Jeremy Agresti