Abstract: Droplet interfaces are formed between droplets in an electro-wetting device comprising an array of actuation electrodes. Actuation signals are applied to selected actuation electrodes to place the droplets into an energised state in which the shape of the droplets is modified compared to a shape of the droplets in a lower energy state and to bring the two droplets into proximity. The actuation signals are then changed to lower the energy of the droplets into the lower energy state so that the droplets relax into the gap and the two droplets contact each other thereby forming a droplet interface. The use of sensing electrodes in the device permit electrical current measurements across the droplet interface. The sensing electrodes can be used for either (i) applying a reference signal during droplet actuation or (ii) recording electrical current measurements.

Abstract: There are provided apparatuses for controlling insertion of a membrane channel into a membrane, comprising: a first bath for holding a first liquid in contact with a first surface of the membrane; a second bath for holding a second liquid in contact with a second surface of the membrane, wherein the membrane separates the first and second liquids; a first electrode configured to contact the first liquid; a second electrode configured to contact the second liquid; and a driving circuit configured to apply a potential difference across the membrane via the first and second electrodes to promote insertion of a membrane channel into the membrane from the first liquid or the second liquid. Various configurations of the driving circuit are described that allow effective promotion of membrane channel insertion while reducing the risk of damage to the membrane. Corresponding methods are also described.

Abstract: An electro-wetting on dielectric (EWOD) device, includes first and second substrates defining a fluid chamber therebetween, a plurality of electro-wetting electrodes on the first substrate, and at least one first electrode and at least two second electrodes on the second substrate. The device further includes a current sensor or sensing a difference between (1) a first current flowing between the first electrode and one of the second electrodes via a first fluid package in the fluid chamber of the EWOD device and (2) a second current flowing between the first electrode and another of the second electrodes via a second fluid package in the fluid chamber of the EWOD device.

Abstract: An electro-wetting on dielectric (EWOD) device, comprises first and second substrates defining a fluid chamber therebetween, a plurality of electro-wetting electrodes on the first substrate, and at least one first electrode and at least two second electrodes on the second substrate. The device further includes a current sensor for sensing a difference between (1) a first current flowing between the first electrode and one of the second electrodes via a first fluid package in the fluid chamber of the EWOD device and (2) a second current flowing between the first electrode and another of the second electrodes via a second fluid package in the fluid chamber of the EWOD device.

Abstract: A microfluidic device performs a method of partitioning droplets from a fluid reservoir containing particles that provides a non-Poissonian distribution of dispensed droplets containing a desired number of particles. Using an electrowetting on dielectric (EWOD) device, droplets are dispensed having a Poissonian distribution of dispensed droplets containing a desired number of particles, and the droplets are interrogated to determine whether each dispensed droplet has a desired number of particles. Droplets that contain the desired number of particles are moved by EWOD operation to a reaction area on the EWOD device, and droplets that do not contain the desired number of particles are rejected and moved by EWOD operation to a holding area on the EWOD device that is different and spaced apart from the reaction area. The result is that droplets in the reaction area have a non-Poissonian distribution of droplets containing the desired number of particles.

Abstract: An electro-wetting on dielectric (EWOD) device, comprises first and second substrates defining a fluid chamber therebetween, a plurality of electro-wetting electrodes on the first substrate, and at least one first electrode and at least two second electrodes on the second substrate. The device further includes a current sensor for sensing a difference between (1) a first current flowing between the first electrode and one of the second electrodes via a first fluid package in the fluid chamber of the EWOD device and (2) a second current flowing between the first electrode and another of the second electrodes via a second fluid package in the fluid chamber of the EWOD device.

Abstract: Droplet interfaces are formed between droplets in an electro-wetting device comprising an array of actuation electrodes. Actuation signals are applied to selected actuation electrodes to place the droplets into an energised state in which the shape of the droplets is modified compared to a shape of the droplets in a lower energy state and to bring the two droplets into proximity. The actuation signals are then changed to lower the energy of the droplets into the lower energy state so that the droplets relax into the gap and the two droplets contact each other thereby forming a droplet interface. The use of sensing electrodes in the device permit electrical current measurements across the droplet interface. The sensing electrodes can be used for either (i) applying a reference signal during droplet actuation or (ii) recording electrical current measurements.

Abstract: Droplet interfaces are formed between droplets in an electro-wetting device comprising an array of actuation electrodes. Actuation signals are applied to selected actuation electrodes to place the droplets into an energised state in which the shape of the droplets is modified compared to a shape of the droplets in a lower energy state and to bring the two droplets into proximity. The actuation signals are then changed to lower the energy of the droplets into the lower energy state so that the droplets relax into the gap and the two droplets contact each other thereby forming a droplet interface. The use of sensing electrodes in the device permit electrical current measurements across the droplet interface. The sensing electrodes can be used for either (i) applying a reference signal during droplet actuation or (ii) recording electrical current measurements.

Abstract: A method of determining the result of an assay in a microfluidic device includes the steps of: dispensing a sample droplet onto a first portion of an electrode array of the microfluidic device; dispensing a reagent droplet onto a second portion of the electrode array of the microfluidic device; controlling actuation voltages applied to the electrode array to mix the sample droplet and the reagent droplet into a product droplet; sensing a dynamic property of the product droplet; and determining an assay of the sample droplet based on the sensed dynamic property. The dynamic property is a physical property of the product droplet that influences a transport property of the product droplet on the electrode array. Example dynamic properties of the product droplet include the moveable state, split-able state, and viscosity based on droplet properties. The method may be used to perform an amoebocyte lysate (LAL) assay.

Abstract: The disclosure provides a method of manipulating droplets in an electro-wetting on dielectric (EWOD) device. Electro-wetting electrodes of the EWOD device are selectively actuated to: cause first and second droplets in a fluid medium in the fluid chamber of the EWOD device to contact each other to form a droplet interface bilayer, the first droplet containing fluid of a first composition including a first solute species and the second droplet containing fluid of a second composition different to the first composition, maintain the first and second droplets contacting each other to maintain the droplet interface bilayer and thereby allow the first solute species to pass from the first droplet to the second droplet via the DIB; and cause the first droplet to separate from the second droplet. This method aspect results in transfer of solute from the first droplet to the second droplet.

Abstract: A method of operating an EWOD device to employs a magnetic field to separate magnetically responsive particles from a polar liquid droplet. The method includes the steps of dispensing a liquid droplet onto an element array of the EWOD device, wherein the liquid droplet includes magnetically responsive particles; performing an electrowetting operation to move the liquid droplet along the element array to a location relative to a magnet element in proximity to that location of the EWOD device; operating the magnet element to apply a magnetic field to the liquid droplet, wherein at least a portion of the magnetically responsive particles aggregate within the liquid droplet in response to the magnetic field; and separating the aggregated magnetically responsive particles from the liquid droplet with the magnetic field, wherein the aggregated magnetically responsive particles move in response to the magnetic field to a location on the element array in proximity to the magnet element.

Abstract: A control method and related apparatus are disclosed for controlling actuation voltages applied to array elements of an element array on an electrowetting on dielectric (EWOD) device, wherein test metrics are determined and employed for optimizing subsequent droplet manipulation operations. The control method includes the steps of: receiving a liquid droplet onto the element array; applying an electrowetting actuation pattern of actuation voltages to actuate the droplet to modify a footprint of the droplet from a first state having an initial footprint to a second state having a modified footprint; sensing the modified footprint with a sensor; determining a test metric from sensing the modified footprint indicative of one or more droplet properties based on a droplet response of the liquid droplet to the electrowetting actuation pattern; and controlling actuation voltages applied to the array elements based on the test metric.

Abstract: A method of partitioning droplets from a fluid reservoir containing particles provides a non-Poissonian distribution of dispensed droplets containing a desired number of particles.

Abstract: A method of partitioning droplets from a fluid reservoir containing particles provides a non-Poissonian distribution of dispensed droplets containing a desired number of particles.

Abstract: A method of determining the result of an assay in a microfluidic device includes the steps of: dispensing a sample droplet onto a first portion of an electrode array of the microfluidic device; dispensing a reagent droplet onto a second portion of the electrode array of the microfluidic device; controlling actuation voltages applied to the electrode array to mix the sample droplet and the reagent droplet into a product droplet; sensing a dynamic property of the product droplet; and determining an assay of the sample droplet based on the sensed dynamic property. The dynamic property is a physical property of the product droplet that influences a transport property of the product droplet on the electrode array. Example dynamic properties of the product droplet include the moveable state, split-able state, and viscosity based on droplet properties. The method may be used to perform an amoebocyte lysate (LAL) assay.

Abstract: A method of determining the result of an assay in a microfluidic device includes the steps of: dispensing a sample droplet onto a first portion of an electrode array of the microfluidic device; dispensing a reagent droplet onto a second portion of the electrode array of the microfluidic device; controlling actuation voltages applied to the electrode array to mix the sample droplet and the reagent droplet into a product droplet; sensing a dynamic property of the product droplet; and determining an assay of the sample droplet based on the sensed dynamic property. The dynamic property is a physical property of the product droplet that influences a transport property of the product droplet on the electrode array. Example dynamic properties of the product droplet include the moveable state, split-able state, and viscosity based on droplet properties. The method may be used to perform an amoebocyte lysate (LAL) assay.

Abstract: An AM-EWOD device includes a plurality of array elements arranged in an array of rows and columns, each of the array elements including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes actuation circuitry configured to apply actuation voltages to the element and/or reference electrodes for actuating the array element, and impedance sensor circuitry configured to sense impedance at the array element electrode to determine a droplet or device property at the array element, the impedance sensor circuitry comprising a sensor capacitor and a sensor readout transistor that outputs an output current for sensing. The sensor capacitor is electrically connected to a gate of the sensor readout transistor such that during a sensing phase a voltage perturbation is coupled through the sensor capacitor (and possibly other circuit elements) to the gate of the sensor readout transistor.

Abstract: A method of operating an active matrix electro-wetting on dielectric (AM-EWOD) device provides for enhanced mutual capacitance sensing using integrated impedance sensing circuitry. Array element circuitry of each array element includes actuation circuitry configured to apply actuation voltages to the array element electrode for actuating the array element, and impedance sensor circuitry integrated into the array element circuitry and configured to sense impedance at the array element electrode. The method of operating includes the steps of: perturbing a voltage applied to the array element electrode of a first array element; coupling the voltage perturbation to the array element electrode of a second array element different from the first array element; and measuring the output current from the sensor readout transistor of the second array element for sensing in response to the voltage perturbation.

Abstract: An AM-EWOD device includes a plurality of array elements arranged in an array of rows and columns; each column including a column addressing line that applies control signals to a corresponding column of array elements, and each row including a row addressing line that applies control signals to a corresponding row of array elements; each array element including an element electrode for receiving an actuation voltage and a switch transistor, wherein the switch transistor is electrically connected between the column addressing line and the element electrode and is switched by the row addressing line; and a column detection circuit comprising an addressing circuit that applies an electrical perturbation during a sensing operation to the column addressing line of an array element being sensed, and a measuring circuit that measures an output signal from one of the column addressing lines, wherein the output signal varies based upon a capacitance present at the element electrode.

Abstract: Droplet interfaces are formed between droplets in an electro-wetting device comprising an array of actuation electrodes. Actuation signals are applied to selected actuation electrodes to place the droplets into an energised state in which the shape of the droplets is modified compared to a shape of the droplets in a lower energy state and to bring the two droplets into proximity. The actuation signals are then changed to lower the energy of the droplets into the lower energy state so that the droplets relax into the gap and the two droplets contact each other thereby forming a droplet interface. The use of sensing electrodes in the device permit electrical current measurements across the droplet interface. The sensing electrodes can be used for either (i) applying a reference signal during droplet actuation or (ii) recording electrical current measurements.