Systems and methods for measuring hemoglobin, G6PD activity, and or bilirubin activity in a sample, including measuring the absorbance of a sample, removing background interfering signals, and quantifying the relevant analyte. Systems and methods for reconstituting a reagent in a droplet actuator. Systems and methods for separating plasma from a whole blood sample on a droplet actuator, including combining a sample droplet with an agglutination reagent droplet and using a novel combination of droplet operations to split the sample into a plasma and an agglutinated red blood cell fraction.

There is provided a heating device to independently and/or effectively heat the micro objects manipulated by a micro apparatus/system, for example the droplets of fluids in an electrowetting on dielectric EWOD device of a microfluidic apparatus. The heating device may include a plurality of micro heaters arranged in an array of rows and columns, and the micro heaters of the heating device may be disposed in relative to the electrode elements of the EWOD device, respectively. Therefore, the micro heaters of the heating device may heat one of the electrode elements of the EWOD device, thereby preventing thermal effect of the micro object on the other electrode elements.

A method and microfluidic device are provided for containing a droplet having an outer surface at a predetermined location. The microfluidic device includes a plate having an upper surface and a central region communicating with the upper surface. The central region is adapted for receiving a droplet of fluid thereon. The central region includes an outer periphery that defines a first fluid constraint configured for discouraging fluid on the central region from flowing therepast. A second fluid constraint extends about the first fluid constraint. The second fluid constraint is configured for discouraging fluid flowing therepast. A third fluid constraint extends about the second fluid constraint. The third fluid constraint configured for discouraging fluid flowing therepast.

An EWOD (or AM-EWOD) device includes a reference electrode and a plurality of array elements, each array element including an array element electrode, and control electronics. In a first mode optimized for EWOD actuation, the control electronics is configured to control a supply of time varying voltages to the array element electrodes and the reference electrode, thereby generating an actuation voltage as a potential difference between voltages at the array element electrodes and the reference electrode. The reference electrode includes a first electrical connection and a second electrical connection. In a second mode, the control electronics further is configured to supply an electrical current flow between the first electrical connection and the second electrical connection to generate resistance heat for controlling temperature of the EWOD device. Control may include sensing a temperature of the EWOD device, and switching between operating in the first or second mode based on the sensed temperature.

A device for dispensing one or more microdroplets is provided. The device comprising a microfluidic chip having an oEWOD structure configured to create an optically-mediated electrowetting (oEWOD) force, the microfluidic chip includes a first region and a second region, wherein said first and second regions are separated by a constriction; wherein the first region is adapted to receive and manipulate one or more microdroplets dispersed in a carrier fluid at first flow rate; and wherein the second region is configured to receive the microdroplet via the constriction from the first region and transfer said microdroplet to an outlet port of the microfluidic chip in a second flow rate; wherein the second region is configured to receive said microdroplet via the constriction from the first region by application of an optically -mediated electrowetting (oEWOD) force; and wherein the second flow rate in the second region is higher than the first flow rate in the first flow region. A method and apparatus for dispensing one or more microdroplets are also provided.

A microfluidic droplet generator that includes a body, an inlet arranged adjacent an upper surface of the body, and a sample reservoir adapted to contain a reservoir fluid that is immiscible in water. The sample reservoir includes a floor and a sidewall coupled to the floor. The floor extends along a horizontal axis and the sidewall extends along a vertical axis substantially perpendicular to the horizontal axis. The microfluidic droplet generator also includes one or more microchannels fluidly connecting the inlet to the sample reservoir. Each of the microchannels includes an inlet end and a reservoir end, and the reservoir end of each of the microchannels intersects the sidewall of the sample reservoir at a location beneath the upper surface of the body.

A microfluidic device can include a plurality of channels defined in a substrate and a plurality of rails defined in a substrate. Each channel can comprise a respective channel inlet, a respective channel outlet, and one or more respective non-miscible fluid inlets fluidly coupled to the channel inlet. Each rail can comprise a rail inlet, and each channel outlet can be coupled to a respective rail inlet. One or more fluids introduced via the channel inlets can form first, second, and third droplets, respectively, and the plurality of rails can comprise first, second, and third rails configured such that droplets disposed on the rails form a tripartite droplet interface bilayer (DIB) network.

Methods and systems for driving an active matrix electrowetting on dielectric device including thin-film-transistors to increase the switching frequency of the propulsion electrodes beyond what is typical for line-by-line active matrix driving. By using a latching circuit, it is possible to selectively switch specific propulsion (pixel) electrodes between an “on” and an “off” state, wherein a propulsion electrode in an “on” state can be driven by a time varying drive voltage on the top electrode that is a much higher frequency than is typically possible with amorphous silicon thin-film-transistor arrays. The faster drive frequency improves the performance of electrowetting devices, especially when used with aqueous droplets having a high ionic strength.

A consumable microfluidic receptacle includes a first sheet and a second sheet. The first sheet is electrically connectable to a ground element. The second sheet is spaced apart from the first plate, wherein the microfluidic receptacle is to receive a liquid droplet between the first and second sheets. The second sheet includes an exterior surface portion to receive releasable contact from an array of individually controllable electrodes of an electrode control element to produce an electric field from the second sheet to the first sheet to selectively pull the liquid droplet through the microfluidic receptacle. The second sheet comprises a conductive-resistant matrix and a plurality of conductive paths spaced apart throughout the matrix and oriented perpendicular to a plane through which second sheet extends.

Described herein are cartridges and devices for operating said cartridges for analyzing a biological sample, such as a blood or saliva sample. Also described herein is an impedance sensor for analyzing a biological sample. Further described herein are methods of determining a cell count or detecting an analyte in a biological sample, which can include transporting the biological sample through a sensor comprising a channel or pore; applying an electrical current or voltage to the channel or pore; detecting an impedance within the channel or pore; and determining a cell count or detecting the analyte based on the detected impedance. Also described herein is an electrowetting electrode array that is configured to transport aqueous solutions using low voltage, such as about 50 volts or less. Further described herein are methods of transporting an aqueous liquid using electrowetting electrodes.