Duke University

Advanced Liquid Logic, Inc.

Leland Stanford Junior University

Richard B Fair

Vamsee K Pamula

Michael G Pollack

Vijay Srinivasan

Allen E Eckhardt

Philip Y Paik

Ramakrishna Sista

Hong Ren

Peter B Griffin

Arjun Sudarsan

Dwayne J Allen

Nan Marie Jokerst

Pramod Kolar

Aditi Dighe

The present invention relates to droplet-based surface modification and washing. According to one embodiment, a method of splitting a droplet is provided, the method including providing a droplet microactuator including a droplet including one or more beads and immobilizing at least one of the one or more beads. The method further includes conducting one or more droplet operations to divide the droplet to yield a set of droplets including a droplet including the one or more immobilized beads and a droplet substantially lacking the one or more immobilized beads.

Droplet-based surface modification and washing

A method comprising effecting a change in a shape of a droplet, wherein the droplet is disposed over a substrate in sensing proximity to a sensor and the droplet has a starting surface area exposed to the sensor; and producing an expanded surface area of the droplet in the sensing proximity exposed to the sensor, wherein the expanded surface area exposed to the sensor is greater than the starting surface area exposed to the sensor.

Droplet actuator devices and methods employing magnetic beads

Microfluidic systems having photodetectors disclosed therein and methods of producing the same are disclosed herein. According to an aspect, a microfluidic system includes a body including an interior wall that at least partially defines an interior space for receipt of fluid. Further, the microfluidic system includes a photodetector disposed on the interior wall and positioned to receive light from fluid in the interior space for generating an electrical signal representative of the received light.

Microfluidic systems having photodetectors disposed therein and methods of producing the same

A method of providing a droplet in contact with a magnetically responsive bead and having a reduced quantity of a substance. The method generally includes the steps of (a) providing a droplet actuator comprising: (i) a substrate comprising electrodes arranged for conducting droplet operations on a surface; (ii) a starting droplet comprising: (1) one or more magnetically responsive beads; (2) a starting quantity of the substance; and (3) a starting volume; (b) magnetically immobilizing the one or more magnetically responsive beads at a location which is at a distance from a target droplet splitting zone; (c) conducting one or more droplet operations comprising droplet dividing operations selected to divide the combined droplet to yield a set of droplets comprising: (i) a droplet comprising substantially all of the one or more magnetically responsive beads and having a decreased quantity of the substance relative to the starting concentration; and (ii) a droplet substantially lacking the magnetically responsive beads.

Methods are provided for manipulating droplets. The methods include providing the droplet on a surface comprising an array of electrodes and a substantially co-planer array of reference elements, wherein the droplet is disposed on a first one of the electrodes, and the droplet at least partially overlaps a second one of the electrodes and an intervening one of the reference elements disposed between the first and second electrodes. The methods further include activating the first and second electrodes to spread at least a portion of the droplet across the second electrode and deactivating the first electrode to move the droplet from the first electrode to the second electrode.

Droplet manipulation device

Apparatuses and methods for manipulating droplets are disclosed. In one embodiment, an apparatus for manipulating droplets is provided, the apparatus including a substrate, multiple arrays of electrodes disposed on the substrate, wherein corresponding electrodes in each array are connected to a common electrical signal, and a dielectric layer disposed on the substrate first side surface and patterned to cover the electrodes.

Apparatuses and methods for manipulating droplets

A method of detecting a target analyte in a sample, including executing electrowetting-mediated droplet operations and thereby: combining one or more immunoassay reagent droplets comprising magnetically-responsive beads having affinity for the target analyte with one or more sample droplets potentially comprising the target analyte to yield a first combined droplet; beginning with the combined droplet, effecting a droplet-based washing protocol to wash the magnetically-responsive beads to yield a first washed droplet comprising the washed magnetically responsive beads; and combining the droplet comprising the washed magnetically responsive beads with a droplet comprising a reporter molecule having affinity for target analyte captured on the magnetically-responsive beads to yield a second combined droplet; beginning with the second combined droplet, effecting a droplet-based washing protocol to wash the magnetically-responsive beads to yield a second washed droplet comprising the washed magnetically responsive beads; detecting a signal from the second washed droplet which corresponds to the presence, absence and/or quantity of the analyte in the sample.

Droplet-based affinity assays

The invention relates to bead incubating and washing on a droplet actuator. Methods for incubating magnetically responsive beads that are labeled with primary antibody, a sample (i.e., analyte), and secondary reporter antibodies on a magnet, on and off a magnet, and completely off a magnet are provided. Also provided are methods for washing magnetically responsive beads using shape-assisted merging of droplets. Also provided are methods for shape-mediated splitting, transporting, and dispensing of a sample droplet that contains magnetically responsive beads. The apparatuses and methods of the invention provide for rapid time to result and optimum detection of an analyte in an immunoassay.

Bead incubation and washing on a droplet actuator

The present invention relates to droplet-based pyrosequencing including a method of identifying a base at a target position in a sample nucleic acid. The method includes: (a) providing a droplet microactuator including a first droplet including a sample nucleic acid immobilized on a bead; and (b) on the droplet microactuator: (i) contacting the first droplet with one or more reagent droplets to yield a second droplet, wherein the one or more reagent droplets include reagents for extending a double stranded portion of the sample nucleic acid by incorporating a nucleotide at the target position; (ii) splitting the second droplet to yield a third droplet including the bead and a fourth droplet lacking the bead; and (iii) assaying the third droplet to determine whether the nucleotide was incorporated at the target position.

Droplet-based pyrosequencing

Droplet manipulation system and method

A method of providing a droplet in contact with a magnetically responsive bead and having a reduced quantity of a substance. The method generally includes the steps of (a) providing a droplet actuator () comprising: (i) a substrate () comprising electrodes () arranged for conducting droplet operations on a surface; (ii) a starting droplet () comprising: (1) one or more magnetically responsive beads (); (2) a starting quantity of the substance; and (3) a starting volume; (b) magnetically immobilizing the one or more magnetically responsive beads at a location which is at a distance from a target droplet splitting zone, (); (c) conducting one or more droplet operations comprising droplet dividing operations selected to divide the combined droplet to yield a set of droplets comprising: (i) a droplet () comprising substantially all of the one or more magnetically responsive beads and having a decreased quantity of the substance relative to the starting concentration; and (ii) a droplet () substantially lacking the magnetically responsive beads.

The present invention relates to filler fluids for droplet operations. According to one embodiment of this aspect, a droplet microactuator is provided and includes: (a) a first substrate comprising electrodes configured for conducting droplet operations on a surface of the substrate; (b) a second substrate spaced from the surface of the substrate by a distance sufficient to define an interior volume between the first substrate and second substrate, wherein the distance is sufficient to contain a droplet disposed in the space on the first substrate; and (c) a droplet arranged in the interior volume and arranged with respect to the electrodes in a manner which permits droplet operations to be effected on the droplet using the electrodes.

Growing community of inventors

Durham, NC, United States of America

Richard B Fair