Devices and methods for blood analysis using electrowetting-on-dielectric

Abstract

In one aspect, the disclosure describes a device for sample analysis. The device includes a movement grid (104) including a top layer and a bottom layer. The bottom layer includes a dielectric layer (114) coated with a bottom hydrophobic layer (118). The top layer includes a conductive top plate (120) coated with a top hydrophobic layer (119). The top layer and the bottom layer define a cavity (126). A plurality of digital microfluidic (DMF) electrodes (106) are configured to selectively actuate regions of the dielectric layer to move a sample droplet (110) within the cavity (126) between regions corresponding to each of the plurality of DMF electrodes (106) via clcctrowctting-on- dielectric forces. The device is configured to move the sample droplet (110) through a filtration site (151) by the plurality of DMF electrodes (106) to at least one sensor (108).

Description

DEVICES AND METHODS FOR BLOOD ANALYSIS USING ELECTROWETTING-ON-DIELECTRICCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims all benefit including priority to U.S. Provisional Patent Application 63 / 552,990, filed 13 February 2024, and entitled “DEVICES AND METHODS FOR BLOOD ANALYSIS USING ELECTROWETTING-ON-DIELECTRIC”, the entire contents of which are hereby incorporated by reference.TECHNICAL FIELD

[0002] The disclosure relates generally to biological analytics, and more particularly to systems and methods for blood plasma analysis.BACKGROUND

[0003] Blood tests are an invaluable tool in the field of healthcare and research. They can be instrumental in determining physiological and biological states. For example they can be used to detect specific components of blood (e.g., glucose, cholesterol, etc.). These blood tests often necessitate blood collection and subsequent processing (if needed) to render quantitative or qualitative analytes.

[0004] Despite the ubiquity of blood tests, they can still prove to be challenging to implement in, for example, an at-home setting without a healthcare practitioner. Furthermore, current methods of conducting complex blood tests (e.g., ones with specific methodologies to produce the relevant analyte) may still leave room for human error. High volumes of sample may make it more challenging to conduct the necessary analysis because the subject may not have sufficient blood to give or may not want to give that much blood. Such considerations can limit the accuracy and / or types of blood tests that can be conducted off of a single collection sample.

[0005] Improvements in the field of blood tests are desirable.SUMMARY

[0006] In one aspect, the disclosure describes a device for sample analysis. The device includes a movement grid including a top layer and a bottom layer. The bottom layer includes adielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity. A plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces. The device also includes at least one sensor configured to measure the sample droplet, at least one filtration site corresponding to at least one filtration DMF electrode of the plurality of DMF electrodes. The device is configured to move the sample droplet into the filtration site by the plurality of DMF electrodes and move the sample droplet out of the filtration site by the plurality of DMF electrodes. The device is configured to move the sample droplet in the movement grid through the at least one filtration site to the at least one sensor.

[0007] In some embodiments, the device is configured to move the sample droplet from a first neighbouring region corresponding to at least one first neighbouring DMF electrode of the plurality of DMF electrodes into the at least one filtration site and from the filtration site to a second neighbouring region corresponding to at least one second neighbouring DMF electrode of the plurality of DMF electrodes.

[0008] In some embodiments, the filtration site includes at least one of a filter material functionalized for specific protein removal, a filter to assist with the precipitation of unwanted substances, a prefabricated filter, and a polymer matrix.

[0009] In some embodiments, the filter material functionalized for specific protein removal comprises biotin / avidin complexes or antibody / aptamer specific targeting.

[0010] In some embodiments, the filter to assist with the precipitation of unwanted substances comprises dextran.

[0011] In some embodiments, the filtration site is held in place by at least one of double-sided tape or friction between the top layer and the bottom layer.

[0012] In some embodiments, edges of the filtration site through which no sample droplet is configured to travel are sealed using a barrier.

[0013] In some embodiments, the barrier is at least one of a hydrophobic barrier, a solid barrier, double-sided tape, and a hydrophobic solution deposited along the edges of the filter.

[0014] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid including a top layer and a bottom layer. The bottom layer includes a dielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity. A plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces. The device also includes at least one sensor configured to measure the sample droplet, and microbeads to trap specific components or to remove precipitated components from the sample droplet. The device is configured to expose the sample droplet to the microbeads and move the sample droplet in the movement grid to the at least one sensor.

[0015] In some embodiments, the device further includes a filtration site to filter the microbeads from the sample droplet.

[0016] In some embodiments, the microbeads are magnetic microbeads, and the device further includes a magnet configured to separate the magnetic microbeads and the sample droplet after exposing the sample droplet to the magnetic microbeads.

[0017] According to a further aspect, there is provided a device for sample analysis. The device includes a sample inlet to receive a sample, and a movement grid comprising a top layer and a bottom layer. The bottom layer includes a dielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity. A plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting- on-dielectric forces. The device also includes at least one sensor configured to analyze the sample droplet. The device is configured to move the sample droplet through the movement grid and to the at least one sensor. A subset of the plurality of DMF electrodes are configured to act as a reservoir electrode capable of dispensing the sample droplet from at least some of the sample.

[0018] In some embodiments, the subset of the plurality of DMF electrodes control sample droplet dispensation based in part on high-fidelity capacitance-based volume sensing.

[0019] In some embodiments, the device can adjust geometry of the reservoir electrode based in part on high-fidelity capacitance-based volume sensing.

[0020] In some embodiments, the subset of the plurality of DMF electrodes is reconfigurable.

[0021] In some embodiments, the reservoir electrode is transferable to another subset of the plurality of DMF electrodes.

[0022] According to a further aspect, there is provided a device for sample analysis. The device includes a sample inlet to receive a sample and provide the sample with hydrophilic contact with transfer paper, and a top layer and a bottom layer. The bottom layer includes a dielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity containing the transfer paper. At least one electrode is configured to selectively actuate the dielectric layer and move the sample via electrowetting-on-dielectric forces. When the sample is provided, the sample contacts the transfer paper and is brought into contact with the top layer and the bottom layer establishing electrical contact with the at least one electrode, and the at least one electrode is actuated to draw the sample out of the transfer paper.

[0023] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid including a top layer and a bottom layer. The bottom layer includes a dielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity. A plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes by electrowetting-on-dielectric forces. The device also includes at least one sensor configured to measure the sample droplet. Breakdown of the dielectric layer corresponding to at least one broken DMF electrode of the plurality of DMF electrodes is detected. The device is configured to move the sample droplet through the movement grid and to the at least one sensor by avoiding the at least one broken DMF electrode.

[0024] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid including a top layer and a bottom layer. The bottom layer includes a dielectric layer coated with a bottom hydrophobic layer. The top layer includes a conductive top plate coated with a top hydrophobic layer. The top layer and the bottom layer define a cavity. A plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces. The device also includesat least one sensor configured to measure the sample droplet. The device is configured to move the sample droplet through the movement grid and to the at least one sensor.

[0025] In some embodiments, at least some gaps between the DMF electrodes are filled with microbeads or fine particulates having high dielectric strength.

[0026] In some embodiments, the microbeads or fine particulates are applied by mixing the microbeads or fine particulates into an evaporating solvent, spraying said mixture onto the movement grid, and wiping excess of the mixture off the movement grid.

[0027] In some embodiments, the microbeads or fine particulates are applied by spreading the microbeads or fine particulates, and wiping excess of the mixture off the movement grid.

[0028] In some embodiments, the height of adjacent DMF electrodes are aligned.

[0029] In some embodiments, the device further includes a reservoir includes a top reservoir layer and a bottom reservoir layer. The bottom reservoir layer includes a dielectric reservoir layer coated with a bottom hydrophobic reservoir layer. The top reservoir layer includes a conductive reservoir top plate coated with a top hydrophobic reservoir layer. The top reservoir layer and the bottom reservoir layer define a cavity. A reservoir digital microfluidic electrode is configured to selectively actuate the reservoir to dispense the sample droplet to the movement grid via electrowetting-on-dielectric forces. The reservoir is defined in part by an integral separation wall.

[0030] Embodiments may include combinations of the above features.

[0031] Further details of these and other aspects of the subject matter of this application will be apparent from the detailed description included below and the drawings.DESCRIPTION OF THE DRAWINGS

[0032] Reference is now made to the accompanying drawings, in which:

[0033] FIG. 1 is a system diagram of an at-home health monitor system, according to some embodiments.

[0034] FIG. 2 is a system diagram of an embodiment analyzer system, according to some embodiments.

[0035] FIG. 3A is a top view of an embodiment analyzer system, according to some embodiments.

[0036] FIG. 3B is a perspective view of an embodiment analyzer system, according to some embodiments.

[0037] FIG. 3C is a side view of an embodiment analyzer system, according to some embodiments.

[0038] FIG. 4 is a perspective view of a chip with digital microfluidic components, according to some embodiments.

[0039] FIG. 5A is a plan view of a chip, according to some embodiments.

[0040] FIG. 5B is a plan view of a chip with a virtual bulk fluid reservoir, according to some embodiments.

[0041] FIG. 6 is a top view of digital microfluidic electrodes with droplets contained thereon, according to some embodiments.

[0042] FIG. 7A is a cross-sectional elevation view of a chip, according to some embodiments.

[0043] FIG. 7B is a cross-sectional elevation view of a chip, according to some embodiments.

[0044] FIG. 8 is a plan view of a chip with reagents provided thereon, according to some embodiments.

[0045] FIG. 9A is a cross-sectional elevation view of a single electrochemical sensor, according to some embodiments.

[0046] FIG. 9B is a cross-sectional elevation view of a multilayer electrochemical sensor, according to some embodiments.

[0047] FIG. 9C is a perspective view of an electrochemical sensor with reagents provided thereon, according to some embodiments.

[0048] FIG. 10A is a plan view of an electrochemical sensor, according to some embodiments.

[0049] FIG. 10B is a plan view of an electrochemical sensor with carbon nano-tubes, according to some embodiments.

[0050] FIG. 11A illustrates a droplet moving from the movement grid to an electrochemical sensor, according to some embodiments.

[0051] FIG. 11B illustrates the movement grid and an electrochemical sensor, according to some embodiments.

[0052] FIG. 12 illustrates a blood plasma separator locking mechanism, according to some embodiments.

[0053] FIG. 13 shows a plan view of a chip with hydrophobic cutter installed thereon, according to some embodiments.

[0054] FIG. 14A shows a plan view of a chip with an example filtration site, according to some embodiments.

[0055] FIG. 14B shows a plan view of a chip with an example filtration site with sealed edges, according to some embodiments.

[0056] FIG. 14C shows a plan view of a chip with microbeads, according to some embodiments.

[0057] FIG. 15A illustrates a dedicated reservoir electrode, according to some embodiments.

[0058] FIG. 15B illustrates a virtual reservoir made up of individual DMF electrodes, according to some embodiments.

[0059] FIG. 16 is a block diagram of a dielectric breakdown detector configuration, according to some embodiments.

[0060] FIG. 17A shows a plan view of the chip indicating the separation walls.

[0061] FIG. 17B shows a perspective view of the chip from FIG. 17A.

[0062] FIG. 18 is a schematic diagram of a computing device, according to some embodiments.DETAILED DESCRIPTION

[0063] Before any embodiments are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways.

[0064] The improvements described herein are generally directed to systems and methods for improved health monitoring hardware and software. The improvements described herein can be used to make at-home health monitoring and blood tests more reliable and robust. In particular, the improvements described herein can be used in systems designed for chip- or cartridge-based analyte tests (e.g., blood or blood plasma) carried out using a testing platform such as an analyzer system.

[0065] Such chip-based testing systems can comprise a sample collection system, an (optionally disposable) chip, and an analyzer system. The sample collection system can be used to collect a sample (e.g., blood plasma) from the subject. The sample may then be provided to the chip housed in the system analyzer. The chip may be configured with various components to analyze the sample which may be operated by the system analyzer. Separation of chip and system analyzer may permit the use of multiple chips (e.g., to carry out different analyses or to minimize contamination between samples). The system may further involve the use of general and / or specialty software embedded within the analyzer, on an app, and / or carried out by cloud computing. When operated, the chip-based system may be capable of carrying out analyses on the sample. Such analysis may be used to diagnose a subject of a condition, monitor various biological metrics or other metrics, or carry out other objectives.

[0066] The sample collection system can be configured to collect a sample (e.g., blood) from the subject. The sample collection system can be configured to carry out specific operations with the sample prior to providing the sample to the chip. For example, the sample collection system may be configured to filter the sample. As a further example, the sample collection system may be configured to carry out plasma separation for blood samples. The sample collection system may further be configured with an adaptor to aid in the provision of the sample to the chip after collection. Such adaptors can ensure that a consistent delivery of sample to the chip which may limitcontamination of the sample by external contaminants or ensure that the sample is delivered in a manner to ensure it will be usable by the chip.

[0067] Aspects of various embodiments are described through reference to the drawings.

[0068] FIG. 1 is a system diagram of an at-home health monitor system 10, according to some embodiments.

[0069] The system 10 can include a chip 100, a user device 200, and an analyzer system 300. The system components can work together to execute a test on a sample collected using the sample collection system described above. For example, a user may be able to detect the type of the chip 100 (e.g., the type of test executable by the chip or the configuration of the tests on the chip 100). The user may be able to detect this from the chip 100, for example, by scanning a barcode, QR code, RFID tag (e.g., NFC), or EEPROM on the chip using the user device 200. Alternatively, the user may be asked to input a code on the chip 100 into the user device 200. The user may then place the chip 100 or otherwise insert the chip 100 into the analyzer system 300. The user device 200 may then select or otherwise determine the microfluidic operations sequences from the chip type of chip 100 and transmit the microfluidic operations sequence to the analyzer system 300 to carry out the testing on a sample. The analyzer system 300 may be configured to transmit the test results back to the user device 200.

[0070] In some embodiments, the user device 200 may include a processor 202, a memory 204, an I / O interface 206, and a network interface 208. The user device may be configured to detect or receive a chip type (e.g., a chip ID) from the chip 100 by, for example, scanning with the user device 200 or input by the user (e.g., by the I / O interface 206). In alternative embodiments, the chip type may be detected by the analyzer system 300 when the chip 100 is therein inserted and this information may be transmitted to the user device 200 using the network interface 208. The user device 200 determines the microfluidic operations sequence based on the chip type. The user device 200 may pull the operations from the memory 204 or it may communicate with an external server (not shown) to pull the operations. The user device 200 may transmit these instructions to the analyzer system 300 using the network interface 208. While or after carrying out the microfluidic operations sequence, the analyzer system 300 may transmit per-channel raw electrochemical data (or error data as the case may be) to the user device 200. The user device 200 may be configured to process the data received from the analyzer system 300 and provide the user (or another third party) with results of the test.

[0071] In some embodiments, the analyzer system 300 may be configured to carry out instructions received by the user device 200 and provide results from the sensors to the user device 200. In some embodiments, the analyzer system 300 may be configured to carry out some processing operations onboard its own system (e.g., microfluidic operations sequence processing, basic fault-tolerance operations, some analytical processing, etc.). It is to be understood that the processes described herein as occurring on the user device 200 or the analyzer system 300 may equally be carried out by or in conjunction with the opposite component.

[0072] In some embodiments, the user device 200 may be configured to transmit and receive information from an external server (not shown). This may be used to upload test results data from the user device 200 or download software updates onto the user device 200. In some embodiments, the user device 200 may be configured to transmit software updates to the analyzer system 300. In some embodiments, the analyzer system 300 may be configured to communicate directly with an external server.

[0073] The processor 202 may include an app 210 configured to execute operations related to testing and orchestrating the functionality described herein. The processor 202 may include details and variations as described below with reference to the processor 1802 of FIG. 18 below.

[0074] The app 210 may be configured to receive the chip type (e.g., by scanning the chip 100, by user input, or through information received from the analyzer system 300), instruct the analyzer system 300 to carry out a test by transmitting microfluidic operations sequences, receive information (e.g., per-channel electrochemical data) from the analyzer system 300, and present the results to the user. The app 210 may further be configured to receive updates from an external server and (where appropriate) push those to the analyzer system 300.

[0075] The memory 204 may be configured to store information related to the operation of the system. For example, the memory 204 may store microfluidic operations sequences associated with a plurality of chip types. The memory 204 may further store information related to a user profile which may be used to present data to a user with their preferences therein input, or with historical results presented therein. The memory 204 may include details and variations as described below with reference to the memory 1804 of FIG. 18 below.

[0076] The I / O interface 206 may include interfaces to enable the user device 200 to interface with user inputs (e.g., keyboards, buttons, touchpads, switches, etc.) and outputs (e.g., screens,indicators, etc.). The I / O interface 206 may include details and variations as described below with reference to I / O interface 1806 of FIG. 18 below.

[0077] The network interface 208 may connect the user device 200 to other system components. For example, the user device 200 may be configured to communicate with an external device (e.g., the analyzer system 300) to deliver controls or receive results. As another example, the user device 200 may be configured to receive updates from, for example, a server or transmit data (user results, error reports, etc.) to the server. The network interface 208 may include details and variations as described below with reference to the network interface 1808 of FIG. 18 below.

[0078] FIG. 2 is a system diagram of an embodiment analyzer system 300, according to some embodiments.

[0079] The analyzer system 300 may include a processor 302, a memory 304, and a chip interface 306. The analyzer system 300 may further optionally include one or more of an I / O interface 308 and a network interface 310. The analyzer system 300 may be configured with a housing. The housing may be configured to physically receive a chip 100 (e.g., with the cinching mechanism 316). The chip 100, when received, may communicate with the analyzer system 300 through, for example, the chip interface 306. The chip 100 and the analyzer system 300 may communicate to enable the chip 100 to transmit information about its systems (e.g., type of chip, feedback, signals, etc.) and the analyzer system 300 to transmit instructions to the chip 100.

[0080] The processor 302 may include a digital microfluidics (DMF) controller 312. The processor 302 may be configured to transmit (e.g., send or receive) data using any one or more of the chip interface 306, I / O interface 308, and network interface 310. The processor 302 may be configured to pull instructions from the memory 304 or from another component (e.g., an external device or the cloud). The processor 302 may be configured to pull and execute different instructions and / or modify instructions based on several factors (e.g., the type of chip therein inserted, user instructions, the test panel to be performed, updates from an external device or the cloud, calibrations steps, etc.). The processor 302 may include details and variations as described below with reference to the processor 1802 of FIG. 18 below.

[0081] The DMF controller 312 may be used to perform microfluidic operations on the chip 100. The DMF controller 312 may be configured to dispense droplets 110 (e.g., sample droplets) from the reservoir 102, move them between DMF electrodes 106, and conduct mixing operations. TheDMF controller 312 may be configured to validate movement of the droplets 110 and provide some error correction.

[0082] The chip 100 (as described in greater detail below) may comprise, for example, a sandwich consisting of an area array of droplet-sized cells on the bottom, a cavity for droplets in the middle, and a continuous backplane which extends over all individual cells on the top. The cells and the backplane may be electrically insulated from the droplets by, for example, a thin coating. Droplets 110 can be induced to move from one cell region to another adjacent cell region through specific application of electrical forces (e.g., application of an alternating high voltage between an individual cell and the backplane). The DMF controller 312 can manipulate droplets 110 (e.g., microdroplets) on a platform by controlling a set of insulated electrodes. The DMF controller 312 can control the electronics in the chip 100 to drive movement of the droplets 110 across the chip 100 as needed.

[0083] In some embodiments, the chip 100 may have different configurations, sizes, and shapes of electrodes which may vary from chip to chip. Furthermore, the chip 100 may include other structures to alter droplet movement. Reagents printed on the chip 100 may be varied. The DMF controller 312 may be configured to manipulate droplets 110 on different chips 100 depending on that chip’s 100 configuration, size, and shape of the electrodes and other factors.

[0084] When a polar liquid (e.g., blood plasma or water) sits atop a hydrophobic surface it will form into a droplet under surface tension. This orientation helps the liquid minimize the surface area with the hydrophobic surface. A drop of polar liquid sitting atop a hydrophilic surface will spread out and attempt to wet the surface.

[0085] The hydrophobicity of the surface can be modulated using electrical fields. For example, by placing a droplet 110 on a surface with an electrode thereunder, the electrode can modulate the electric fields applied to the droplet 110 thereby modulating the effective hydrophobicity / hydrophilicity of the surface. This process is called electrowetting-on-dielectric (EWOD). By modulating the electric fields of two adjacent cells in an array of cells, the DMF controller 312 can manipulate a droplet 110 to move between these surfaces.

[0086] The DMF controller 312 may further be configured to monitor feedback from a droplet 110 as it moves (or does not move) to validate and correct any deviations in intended movement patterns. Furthermore, this feedback can be used to verify droplet position and volumes. This may be convenient for fault-tolerant microfluidic operations. Moving droplets 110 may not alwayssucceed and it is beneficial if the system 300 can correct itself rather than necessitating a new sample entirely. Viscous fluids (e.g., diluted plasma) may be especially difficult to control with microfluidics.

[0087] Droplet feedback systems can include, for example, a camera with, for example, computer-vision-aided tracking. These cameras however may be expensive and difficult to clean. This may make other more economical droplet feedback systems preferable for consumer products.

[0088] In one implementation, the DMF controller 312 can be configured to detect the presence of a volume of liquid on a surface. In such implementations, the DMF controller 312 can detect whether a set volume of liquid is present on a goal DMF electrode (which may be one in a series of goal DMF electrodes for complex or long range movement patterns). If the set volume is not detected, then the DMF controller 312 can carry out the operation again until, for example, the droplet 110 moves.

[0089] In another implementation, the DMF controller 312 can be configured to rely on capacitive feedback from a droplet 110 on the DMF electrode. For example, the DMF controller 312 may apply a transient DC voltage to each DMF electrode which results in a pulse with an amplitude roughly proportional to the droplet volume. Using these amplitudes, more precise measurement of volume of the droplet 110 can be obtained on a DMF electrode-by-electrode basis.

[0090] The analyzer system 300 includes a potentiostat 314 configured to control and receive signals from one or more electrochemical sensors on an inserted chip 100. The potentiostat 314 may be configured to perform, for example, assays using potentiodynamic operations such as, for example, cyclic-voltammetry (CV) or chronoamperometry (CA). The potentiostat 314 may also be configured to perform other electroanalytical methods.

[0091] The DMF controller 312 may be configured to transport droplets 110 to an electrochemical sensor and the potentiostat 314 may be configured to carry out an electrochemical operation on the droplet 110. For example, the potentiostat 314 may be configured to apply specific and / or dynamic voltages to the sample and facilitate measurement of the electrical characteristics (such as current).

[0092] The memory 304 may store instructions executable by the analyzer system 300. For example, the memory 304 may store instructions for a variety of different types of chips 100 andmay select which instructions to execute based on, for example, the type of chip 100 inserted, a selection made by the user on the analyzer system 300, a selection made by the user on an external device, or some other method. The memory 304 may include details and variations as described below with reference to the memory 1804 of FIG. 18 below.

[0093] The chip interface 306 may be configured to interface with any chips 100 inserted or otherwise connected to the analyzer system 300. For example, a chip 100 may be seated within the analyzer system 300 and the chip 100 may be connected to the analyzer system 300. In particular, the DMF controller 312 may be connected to the DMF control system on the chip 100 and the potentiostat 314 may be connected to the electrochemical sensors on the chip 100. The chip interface 306 may include a single interface through which all connections are made or it may include a plurality of connections. The connection may be physical (enabling the analyzer system 300 to apply electrical forces through the chip 100) or it may be remote (for example, the analyzer system 300 activates the components in the chip 100 via a remote connection).

[0094] The I / O interface 308 may include interfaces to enable the analyzer system 300 to interface with user inputs (e.g., keyboards, buttons, touchpads, switches, etc.) and outputs (e.g., screens, indicators, etc.). The I / O interface 308 may include details and variations as described below with reference to I / O interface 1806 of FIG. 18 below.

[0095] The network interface 310 may connect the analyzer system 300 to other system components. For example, the analyzer system 300 may be configured to communicate with an external device (e.g., an users mobile phone running an app) to deliver results or receive controls. As another example, the analyzer system 300 may be configured to receive updates from, for example, a server or transmit data (user results, error reports, etc.) to a server. The network interface 310 may include details and variations as described below with reference to the network interface 1808 of FIG. 18 below.

[0096] The analyzer system 300 may further comprise other optional components. For example, it may be configured with a vibrating component to vibrate the analyzer system 300 or parts thereof, for example, to dislodge a pinned droplet.

[0097] FIG. 3A is a top view of an embodiment analyzer system 300, according to some embodiments. FIG. 3B is a perspective view of an embodiment analyzer system, 300 according to some embodiments.

[0098] An example chip 100 is illustrated as being in the analyzer system 300. As described above, the system analyzer 300 may be configured to interface with the chip 100 through a chip interface 306 to drive the digital microfluidic operations and / or to drive and receive information about the electrochemical sensors.

[0099] FIG. 3C is a side view of an embodiment analyzer system 300, according to some embodiments.

[0100] In some embodiments, a cinching mechanism 316 can couple the chip 100 with the analyzer 300 to help ensure electrical contact between the chip 100 and the analyzer 300. The cinching mechanism 316 can include a cinching motor 318, a cinching cam 320, and a moving platform 322. After being inserted into the analyzer 300, the chip 100 can be clamped in place. For example, the cinching motor 318 may actuate the cinching cam 320 and the moving platform 322. The moving platform 322 can push down on the chip 100. The moving platform’s 322 vertical position is set by the rotational position of a cinching cam 320 which can be powered by the cinching motor 318. Once cinched, pins on the bottom of the chip 100 may be in electrical contact with the analyzer's 300 pins. In some embodiments, the pins may be stationary. In some embodiments, the pins may be spring-loaded.

[0101] FIG. 4 is a perspective view of a chip 100 with digital microfluidic components, according to some embodiments.

[0102] The chip 100 (e.g., which may also be referred to herein as a cartridge) can comprise digital microfluidic components enclosed within a sealed cartridge. The digital microfluidic components can be used to manipulate droplets 110 (e.g., of a sample of blood or plasma thereof) within the enclosed space and to maneuver droplets 110 to reagents and sensor cells. The chip 100 may enclose the samples in an enclosed system that can be, for example, sealed from outside air or resist leakage of internal liquids.

[0103] FIG. 5A is a plan view of a chip 100, according to some embodiments.

[0104] The chip 100 includes a reservoir 102, a movement grid 104, and electrochemical sensors 108. As described above, the DMF components may connect or couple with an analyzer system 300 such that the analyzer system 300 can control the digital microfluidics on the chip 100 and sense and control the electrochemical sensors 108.

[0105] Samples may be provided to the chip 100 at or near the reservoir 102. The reservoir 102 may use electrowetting forces to hold a bulk sample in place and to deliver droplets 110 of the sample to the movement grid 104 for further operations.

[0106] The movement grid 104 includes a plurality of DMF electrodes 106. In some embodiments, the DMF electrodes 106 can be identical in construction or can be designed with specific regional functions. In some embodiments, a DMF controller 312 may be configured to selectively activate one or more of the DMF electrodes 106 to drive movement of a droplet 110 from DMF electrode 106 to DMF electrode 106. The movement grid 104 may also include deposits of any reagents, for example, stored in dry form on a particular DMF electrode 106 (described in greater detail below). During use, the movement grid 104 may receive or take a droplet 110 from the reservoir 102, move it using the DMF electrodes 106, optionally mix the droplet 110 with a reagent stored on a particular DMF electrode 106, and bring the droplet 110 to an electrochemical sensor 108 for analysis.

[0107] The reservoir 102 can include two regions 102a and 102b. The first region 102a may be configured to receive the sample (e.g., a diluted plasma sample). The second region 102b may be configured to aliquot a droplet by pulling it and then pinching it off from the main reservoir bulk (e.g., region 102a). The regions 102a and 102b may include electrodes to carry out their intended purpose. Other configurations for the reservoir 102 are possible.

[0108] The electrochemical sensors 108 may include electrodes capable of monitoring and / or driving electroanalytical processes. There are twelve electrochemical sensors 108 shown on chip 100 (six along the top and six along the bottom). Other configurations are possible. In some embodiments, a potentiostat 314 can control the electrochemical sensors 108. Though described as electrochemical sensors 108, one or all of the sensors 108 may be configured for different sensor modalities.

[0109] Though one particular embodiment of the reservoir 102, movement grid 104, and electrochemical sensors 108 is illustrated, many more configurations are possible without deviating from the teachings of the present disclosure.

[0110] FIG. 5B is a plan view of a chip 100 with a virtual bulk fluid reservoir 142, according to some embodiments.

[0111] In some embodiments, the functionality bulk fluid reservoir 102 can be replaced with a virtual bulk fluid reservoir 142 which will be described in greater detail below with reference to FIG. 15A and FIG. 15B.

[0112] The virtual reservoir 142 illustrated in FIG. 5B is larger (and specifically longer) than the reservoir 102 as illustrated in FIG. 5A. The larger reservoir 142 can hold a larger volume of sample liquid and it can also enable more dispensing strategies without encroaching on the movement grid 104. The larger reservoir 142 can allow the blood collector geometry (e.g., blood plasma separator 500) to sit outside the analyzer 300. Distancing the blood collector geometry from the analyzer 300 may be beneficial as it may reduce the risk of incompatibility as between the blood collector and the analyzer 300 should the blood collector be updated (e.g., newer versions of the blood collector can be developed without as much risk that it may not be usable with older models of an analyzer 300, for example due to spatial hindrance). While these advantages are described with reference to a virtual reservoir 142, these advantages may also be achieved with a standard reservoir 102 as well.

[0113] FIG. 6 is a top view of digital microfluidic electrodes 106 with droplets contained thereon, according to some embodiments.

[0114] By manipulating the electrical forces surrounding the individual DMF electrodes 106, the droplets 110 may be compelled to move between adjacent DMF electrodes 106 or stay in place.

[0115] FIG. 7A is a cross-sectional elevation view of a chip 100 across line A-A (FIG. 5A), according to some embodiments.

[0116] FIG. 7B is a cross-sectional elevation view of a chip 100 across line A-A (FIG. 5A), according to some embodiments.

[0117] The chip 100 may include a printed circuit board (PCB) 112, a dielectric layer 114, a bottom hydrophobic coating 118, an adhesive 116, a top hydrophobic coating 119, a top plate 120, and an enclosure 122 defining a cavity 126 for a sample droplet 110. An ITO spacer 127 may also define the cavity 126. The chip 100 may also include an EC spacer 124, an ITO spacer 127, and electrochemical sensors 108.

[0118] The PCB 112 may comprise a printed circuit board with or without solder mask. The PCB 112 can be divided into DMF electrodes 106 for droplet movement and microfluidic operations and, for example, electrochemical sensor 108 electrodes for running assays (as seen in FIG. 5A).The electrodes may be coated using an immersion gold process with a protective layer such as palladium beneath to improve electrochemical signal reliability and resist corrosion during storage.

[0119] The dielectric layer 114 may be used to induce electrowetting-on-dielectric, the phenomenon that allows for droplet 110 movement on the grid. In some embodiments, the dielectric layer 114 can be a UV / heat curable liquid with a high dielectric strength. Thickness of the dielectric layer 114 may be controlled by the fabrication process used such as spin coating, dip coating, etc. In some embodiments, 2.5 pm thick polyester film can be used. In some embodiments, 10 pm thick polyester film can be used. In some embodiments, 7.5 pm polyimide film can be used. In some embodiments, the dielectric layer 114 may be 5-10 pm thick. In some embodiments, the dielectric layer 114 may be 10 pm thick. Thinner dielectric layers can enable droplet movement at lower actuation voltages. The dielectric layer 114 is bonded to the PCB 112 using an adhesive 116. In some embodiments, the adhesive 116 is an adhesive coating applied to one side of the PCB 112.

[0120] Hydrophobic coatings 118, 119 may be used to coat the dielectric layer 114 and top plate 120 to aid droplet 110 movement and create the contact angle required for movement by electrowetting-on-dielectric. In some embodiments, Cytonix Fluoropel PFC 1101V can be used. After coating the dielectric layer 114, the Fluoropel can be cured. The thickness of the hydrophobic coatings 118, 119 may be less than one micrometer.

[0121] ITO spacer 127 (which may be a spacing adhesive) can be used to hold the top plate 120 in place and provide enough space for the droplets 110 to move underneath. In some embodiments, the spacer 127 height may be between 100 and 300 micrometers. In one specific embodiment, the spacing may be approximately 235 pm.

[0122] The top plate 120 can be a conductive top plate to close the circuit through the PCB 112, dielectric layer 114, and droplets 110. In some embodiments, the top plate 120 can be connected to the base PCB 112 using a deformable conductive material (e.g., copper tape) at, for example, the edge. In some embodiments, the top plate 120 may be Indium-Tin-Oxide (ITO)-coated glass. Transparency allows the droplets 110 to be seen during movement. Other conductive rigid materials such as materials of another PCB or injection molded conductive parts may be used when direct visual contact with the droplets 110 is not required.

[0123] Enclosure 122 can provide a sealed case to seal any reagents (described in greater detail below) and hydrophobic coatings 118 and 119 inside the chip 100 for safe handling and disposal by consumers.

[0124] On the periphery of the chip 100 are the electrochemical sensors 108. The electrochemical sensors 108 may optionally interoperate with the EC spacer 124 and hydrophilic layers 136 to receive sample. In some embodiments, the electrochemical sensors 108 do not use hydrophilic layers 136 to receive the sample (e.g., the hydrophobic coating 119 and / or 118 may be masked to encourage the sample droplet 110 to enter the sensor 108), as seen in FIG. 7A. In some embodiments, the EC spacer 124 provides a region for the electrochemical reaction to be carried out. In some embodiments, the hydrophilic layers 136 can attract the sample droplet 110 into the sensor 108. In some embodiments, the hydrophilic layers 136 can overlap on the hydrophobic coating 118 (seen in the bottom hydrophilic layer 136 of FIG. 7B). This may advantageously improve the reliability of the sensors 108 by improving droplet transfer. The electrochemical sensors 108 are described in greater detail below.

[0125] FIG. 8 is a plan view of a chip 100 with reagents 128 provided thereon, according to some embodiments.

[0126] In some embodiments, some chips 100 may include deposited reagents 128 (inclusive of reagents 128a, 128b, and 128c). These reagents 128 may be any reagents required to be mixed into plasma / diluent droplets 110 before moving to the electrochemical sensors 108 (inclusive of sensors 108a and 108b). In some embodiments, different reagents 128 may be placed on the grid which may ultimately be tested by different electrochemical sensors 108 testing for different analytes or phenomena. For example, one droplet 110 may be directed to mix with reagent 128a and then analyzed by sensor 108a while another droplet 110 may be directed to mix with reagent 128b, made to wait while a reaction occurs, mixed with reagent 128c, and analyzed by sensor 108b which may be configured differently than sensor 108a. Example reagents sensors 108 can include electrochemical sensors, dilution factor sensors, total cholesterol (TC) sensors, high-density lipoprotein (HDL) sensors, and triglyceride (TRG) sensors. Furthermore, some sensors 108 may be coated with coatings or otherwise configured to carry out a particular analysis.

[0127] FIG. 9A is a cross-sectional elevation view of a single electrochemical sensor 108 across line B-B (FIG. 5A), according to some embodiments.

[0128] The electrochemical sensor 108 may be provided on a PCB 112. The electrochemical sensor 108 may comprise a three-electrode set up with a working electrode 130, a counter electrode 132, and a reference electrode 134. Other electrode set ups are conceived (e.g., a counter electrode 132 split into two halves 132A and 132B). The electrochemical sensor 108 maybe situated underneath one or more hydrophilic layers 136. In some embodiments, this may include a multi-layered assembly that creates a cavity with the electrodes exposed to the liquid. The assembly may consist of multiple hydrophilic layers 136, spacer adhesives 124 composed of double and / or single sided tapes (shown in FIG. 9B). The hydrophilic layers 136 could be natively hydrophilic, or made hydrophilic through the addition of different liquids dried on the surface such as sugars, salts, surfactants, hydrogels, etc. The working electrode 130 may, in some embodiments, be coated with a coating 131 , for example a membrane that may, for example be enzyme modified. The droplet reaction mixture 138 (e.g., a plasma reaction mixture) may be situated on the working electrode and be analyzed by the electrochemical sensor 108. The coating 131 may include a porous membrane. This porous membrane may be deposited on the working electrode 130 using a deposition printer. The coating 131 may contain enzymes, antibodies, and reagents as required.

[0129] As described above, the electrochemical sensor 108 may be made to perform, for example, assays using potentiodynamic operations such as, for example, cyclic-voltammetry (CV) or chronoamperometry (CA). Other electroanalytical methods are conceived. Other electrochemical operations are conceived of as being carried out with the electrochemical sensor 108 such as applying specific and / or dynamic voltages to the sample and measuring the current observed. The electrochemical sensor 108 may be controlled by a potentiostat 314 on an analyzer system 300.

[0130] FIG. 9B is a cross-sectional elevation view of a multilayer electrochemical sensor 108, according to some embodiments.

[0131] Precipitating certain sample components (e.g. cholesterols) on the movement grid 104 can degrade movement (up to and including a complete stop or "pinning") in the vicinity due to accelerated biofouling of the electrowetting surface. Using a hydrophilic layer 136 such as an EC mesh to precipitate e.g. cholesterols instead of carrying the precipitation out on the movement grid 104 can obviate the issue of degraded movement because the droplet 110 is already in its final resting place and there is no need to move it away from that location afterwards. For example, the sample droplet 110 may be drawn into the upper droplet reaction mixture portion 138 by the upper hydrophilic layer 136, react with a reagent doped in the lower hydrophobic layer 136 to precipitate a component of the sample droplet 110, be drawn into the lower droplet reaction mixture portion 138 by the lower hydrophobic layer 136 to contact the working electrode 130.

[0132] FIG. 9C is a perspective view of an electrochemical sensor 108 with reagents provided thereon, according to some embodiments.

[0133] In some embodiments, the hydrophilic layers 136 can also be loaded with reagents. This can enable the reagents to be mixed directly above the sensor 108. In some embodiments, a hydrophilic layer 136 may be in contact with the electrochemical sensor 108 (cell A). In some embodiments, the hydrophilic layers 136 may both be above the electrochemical sensor 108 (cell B). In some embodiments, the hydrophilic layers 136 may be above the electrochemical sensor 108 in much closer proximity to it (cell C). The heights may vary.

[0134] FIG. 10A is a plan view of an electrochemical sensor 108, according to some embodiments.

[0135] The electrochemical sensor 108 may be configured with a three-electrode set up. The electrochemical sensor 108 may be configured with a circular central working electrode 130, and a counter electrode 132, and a reference electrode 134.

[0136] The electrochemical sensor 108 may include gold. Standard PCB manufacturing techniques may be used. The electrochemical sensor 108 may have many sizes and shapes / numbers of electrodes while falling within the teachings of this description.

[0137] The electrochemical sensor 108 may include a reservoir made up of a small cut-out in, for example, a Fluoropel layer above the electrodes to allow a microdroplet of fluid to sit on the electrode.

[0138] FIG. 10B is a plan view of an electrochemical sensor 108 with carbon nano-tubes 133, according to some embodiments.

[0139] Providing a carbon nano-tube porous ink 133 to the electrochemical sensor 108 can help entrap active biorecognition elements and other reagents within the vicinity of the working electrode 130 while enhancing the stability of the electrochemical sensor 108. The counter electrode 132 can be split in two halves 132A and 132B. The porous ink (membrane) 133 can consist of a binder, such as hydroxyethyl cellulose and / or cellulose acetate, to encapsulate the active biorecognition elements such as enzymes, antibodies, aptamers, and / or DNA probes; cofactors such as ATP, magnesium chloride, magnesium sulfate, magnesium acetate, and / or NAD(P)H; stabilizers, such as bovine serum albumin (BSA), lactose, D-mannitol and / or trehalose; electron mediator, such as potassium ferrocyanide, potassium ferricyanide, methylene blue, 1-methoxy-5-methylphenazinium methyl sulfate (MPMS) and / or ruthenium hexamine; functionalized multi-walled carbon nanotubes (MWCNTs), polyaniline (PANI) and / or functionalized gold nanoparticles to enhance the active surface area of the working electrode 130; and non-ionic surfactant, such as Tween20, and / or Triton™ X-100, to facilitate the homogeneous dispersion of reagent on the working electrode 130.

[0140] FIG. 11A illustrates a droplet 110 moving from the movement grid 104 to an electrochemical sensor 108, according to some embodiments.

[0141] Fluid transfer from the DMF grid 104 to the electrochemical sensor 108 may be accomplished by masking the chip before applying the hydrophobic coating during fabrication to create a hydrophilic cut-out that draws droplets 110 onto the electrode surface. In some embodiments, vibrational forces may be applied to move the droplet 110.

[0142] FIG. 11B illustrates the movement grid 104 and electrochemical sensors 108 with a cutout 146, according to some embodiments.

[0143] Adding a cutout 146 can reduce the chances of a bubble forming on top of the electrochemical sensor 108. Bubbles can displace sample fluid 110 which prevents good signal determination and thus preventing bubbles can be beneficial. Bubbles can also pop, for example, mid-measurement and perturb on ongoing reaction.

[0144] In some embodiments, potential advantages of bifurcating the analyzer system 300 and the chip 100 may be that the components required for controlling and carrying sample testing out can be reused while components that contact the sample or that are depleted or contaminated by sample testing can be replaced. This can enable reuse of some components (one analyzer system 300 can be reused). This can further enable compatibility with a plurality of chips 100 (e.g., different chips 100 may be configured for different test panels) that do not require expert set up or cleaning between uses (chips 100 can be manufactured such that users need not apportion reagents or clean the chips 100 during or after use).

[0145] As described above, in some embodiments, a chip 100 and an analyzer system 300 may be integral to one another without deviating from the teachings of this disclosure. For example, a system which is configured to run the provision of sample testing and the specific sample testing components may be carried out in one integral component. Such integral implementations may, forexample, be configured for single uses or may be configured to be replenished or otherwise reconfigured and subsequently reused.

[0146] The systems and methods described herein can be accomplished using external devices and servers. For example, an analyzer system 300 may communicate results of testing to an external device once the testing is complete or it may receive updates or instructions from a server. The systems and methods described herein can be compatible within broader healthcare treatment solutions.

[0147] Injecting Collected Sample onto the Reservoir Electrode.

[0148] Injecting or inserting the sample onto the chip 100 can be vital to ensuring that the sample is captured by the reservoir 102 for subsequent dispensation. Furthermore, the sample may be filtered during the injection process. Such features may improve the sample retention (thus enabling reduced sample volume extractions) and enhance filtration (which may be beneficial in some embodiments). Furthermore, sample injection may be impeded by capillary lock.

[0149] FIG. 12 illustrates a blood plasma separator locking mechanism 400, according to some embodiments.

[0150] In some embodiments, a locking mechanism 400 may be used to secure the blood plasma separator 500 to, for example, ensure proper placement and to provide a straightforward means of sample injection. The blood plasma separator 500 may comprise a separation filter 502 to separate plasma from red blood cells.

[0151] The locking mechanism 400 may include a holder 402 and a filter lock 404. The holder 402 may be fabricated by, for example, 3D printing methods. The filter lock 404 may be, for example, a mechanical filter lock. This can be used to hold the separation filter 502 in place during plasma filtration and / or sample insertion. The filter lock 404 may prevent leakage from the sides of the separation filter.

[0152] As illustrated, the chip 100 can include transfer paper 140 at the insertion point which can be sandwiched between a bottom plate and a top plate. The transfer paper 140 may include, for example, P8 grade filter paper or Whatman Fusion 5 filter paper. The bottom plate can include a hydrophobic layer 118 to repel the sample, a dielectric layer 114 to modulate the electrical forces applied to the sample (e.g., the EWOD forces), a DMF reservoir electrode to act as a reservoir 102for the sample, and the printed circuit board for DMF 112. The top layer may include a top hydrophobic coating 119 and a conductive top plate for DMF 120.

[0153] The locking mechanism 400 may provide hydrophilic contact with the filter 140 to provide a conduit for the filtered plasma to exit the separation filter 502 using gravity and / or capillary forces. The liquid then comes in contact with a transfer paper 140 that brings the separated plasma in contact with the top hydrophobic layer 119 and bottom hydrophobic layer 118 of the DMF and establish electrical contact with the DMF system. Following electrical contact, electrowetting can be used to draw the plasma out from the transfer paper 140 and onto the DMF.

[0154] In some embodiments, the blood plasma separator 500 may be integral to the chip 100. This may obviate the need for a locking mechanism 400.

[0155] Microfluidic Filtration Through Electrowetting on Dielectric (EWOD).

[0156] FIG. 13 shows a plan view of a chip 100 with hydrophobic cutter 150 installed thereon, according to some embodiments.

[0157] In some embodiments, a hydrophobic cutter 150 may be installed between adjacent DMF electrodes 106. The hydrophobic cutter 150 may be configured to extend in the vertical direction to form a thin cutting implement within the cavity 126. The hydrophobic cutter 150 may be generally flat in a horizontal direction (e.g., thin) or tapered to a cutting end. Other implementations are possible. This hydrophobic cutter 150 can be used to section a droplet 110 off into smaller pieces. For example, a large droplet 110 can be maneuvered to be cut by the hydrophobic cutter 150 (e.g., by moving a large droplet 110 from left to right in the figure to the current location where a smaller portion of the droplet 110 has been sectioned off on the top). The hydrophobic cutter 150 may be made of a material that received a hydrophobic treatment. The hydrophobic cutter 150 may be a paper or it may be a polymer.

[0158] The use of a hydrophobic cutter 150 may be useful to segment a sample droplet 110 which has been treated with reagents 128. Segmenting the sample droplet 110 in this way can allow the full sample droplet 110 to be initially treated with the reagents 128, then the sample droplet 110 is cut, and subsequently the segments can be differently treated (e.g., have different reagents applied and / or sent to different sensors 108). In some embodiments, there may be a plurality of hydrophobic cutters 150 installed on the chip 100 to provide a plurality of locations to segmentsample droplets 110 without risking cross-contamination or to provide a hydrophobic cutter 150 proximate to the locations on the chip 100 to be used.

[0159] FIG. 14A shows a plan view of a chip 100 with an example filtration site 151 , according to some embodiments.

[0160] In some embodiments, one or more DMF electrodes 106 that make up the movement grid 104 may be configured to house a filtration site 151 (e.g., with a filter 152). The filter 152 can be, for example, a size-exclusion filter or a membrane affixed to the surface of the DMF electrode 106. Such configurations can be seen as a variation of a chip 100 with reagents 128 thereon, except rather than providing reagents 128, one or more of the DMF electrodes 106 provides a filtration site 151 for the sample. In other configurations, the filtration site 151 may sit between two DMF electrodes 106 and the droplet 110 may be pulled through as it travels from a first DMF electrode 106 to the next. The separation between two DMF electrodes 106 may be small and the filtration site 151 can overlap onto the adjacent DMF electrodes 106. Other configurations are also possible.

[0161] The filter 152 may be functionalized and used for specific protein removal using, for example, biotin / avidin complexes or antibody / aptamer specific targeting. Droplets 110 may be pretreated with the filter 152 assisting in precipitation of unwanted substrates. For example, dextran may be used to precipitate low-density lipoproteins (LDL) in a high-density lipoprotein (HDL) assay method. In some embodiments, LDL can be precipitated with, for example, dextran sulfate and subsequently blocked with a physical barrier (such as a filter 152).

[0162] Filtration of a fluid on the chip 100 can enable numerous additional assays that may require filtration (e.g., size-exclusion filtration). Furthermore, providing a filtration site 151 within the chip 100 itself can enable a single chip 100 to run tests that require filtrations for, for example, sizeexclusion on the same chip 100 as tests that do not require filtrations, thereby avoiding having to provide two different chips 100 necessitating two separate sample collections from the subject.

[0163] In operation, the sample droplet 110 may be drawn into the filter 152 using EWOD forces between the DMF electrodes 106, for example, as controlled by the DMF controller 312. In some embodiments, a DMF electrode 106 housing a filtration site 151 may preferably neighbour at least two DMF electrodes 106. This can ensure that the sample droplet 110 is drawn into the filtration site 151 from a first neighbouring DMF electrode 106 and pulled out of the filtration site 151 by a second neighbouring DMF electrode 106. This may ensure that the sample droplet 110 is pulled through the filtration site 151 rather than into and out of the same side, which may re-contaminatethe sample droplet 110 with matter that was initially filtered out (though such an implementation may be suitable for some applications). In further preferable embodiments, the sample droplet 110 may enter one side of the filtration site 151 and exit an opposite side which may ensure that the full sample droplet 110 is pulled through a similar filtration volume. The filtration operation may produce some loss or hold-back of droplet volume from the matter left in the filtration site 151.

[0164] In some embodiments, the filtration site 151 is sized such that the sample droplet 110 is not completely retained by the filtration site 151 . Some liquid may be retained by the filtration site 151. If the filtration site 151 is sufficiently large (or the droplet 110 needs to be pulled through a long volume of the filtration site 151) then much or all of the sample droplet 110 may be retained by the filtration site 151 and sufficient sample droplet 110 may be prevented from exiting. Accordingly, in some embodiments, the size (or filtration distance) of the filtration site 151 is configured to release sufficient sample droplet 110 for subsequent steps (e.g., more processes on the movement grid 104 or measurement on the electrochemical sensor 108).

[0165] In some embodiments, the filtration site 151 may include filter paper 152 that is coated in a hydrophobic coating such as, for example, wax or a paraffin wax. Hydrophobic coatings may enable the filter paper 152 to retain less liquid within the filtration site 151.

[0166] The filtration site 151 may be held in place using, for example, double-sided tape to bind to the top plane and hold the filter 152 to the DMF electrode 106 or using mechanical compression using friction to prevent movement. The filtration site 151 may consist of a prefabricated or commercially available filter 152 (Whatman Fusion 5, P8-grade filter paper, etc.), or may consist of a deposited-on-DMF polymer solution, which, for example, dries to form a polymer matrix with desired porosity and swelling characteristics.

[0167] FIG. 14B shows a plan view of a chip 100 with an example filtration site 151 with sealed edges 154, according to some embodiments.

[0168] In some embodiments, one or more DMF electrodes 106 that make up the movement grid 104 may be configured to house a filtration site 151 (e.g., with a filter 152). In some embodiments, the edges 154 of the filtration site 151 that are not for droplet 110 entrance and exit (e.g., sides parallel to the direction of movement of the sample droplet 110 if travelling in a straight line through the filtration site 151) may be sealed using, for example, a hydrophobic barrier such that droplet 110 volume does not escape through unintended sides. The barrier can be a solidmaterial such as a double-sided tape or a hydrophobic solution deposited along the edges of the filter 152. In some embodiments, the barrier may be, for example, wax.

[0169] In some embodiments, the filtration site 151 can be situated immediately in front of the electrochemical sensor 108. In some embodiments, the filtration site 151 can completely cover the entrance to the electrochemical sensor 108 such that no part of the sample droplet 110 can maneuver around the filtration site 151 to reach the electrochemical sensor 108 without being filtered.

[0170] FIG. 14C shows a plan view of a chip 100 with microbeads 153, according to some embodiments.

[0171] Some methods of droplet 110 filtering may use microbeads 153 for filtration. For example, a droplet 110 may be brought to microbeads 153 (e.g., functionalized for a particular reaction) prior to entering electrochemical sensor 108 to drive a reaction, trap specific components for the assay, remove precipitated components and measure a remainder. These microbeads 153 may be resident to a side on the movement grid 104. In some embodiments, the microbeads 153 may suspended in liquid, deposited on the movement grid 104, then the suspension may be dried down to a pellet suitable for, for example, long-term storage before use. In some embodiments, the microbeads 153 comprise a polymeric microbeads such as polystyrene. In some embodiments, the microbeads 153 may have covalently bonded molecules such as antibodies to capture proteins from the sample droplet 110, acting as filter or a concentrator. In some embodiments, the microbeads 153 may be functionalized with polymers capable of interacting with analytes. Moving the sample droplet 110 may separate the microbeads 153 after the reaction if the microbeads 153 stay put. In some embodiments, the sample droplet 110 may be subsequently filtered at a filter site 151 (not shown) to remove the microbeads 153.

[0172] In some embodiments, the microbeads 153 may be magnetic (e.g., paramagnetic microbeads 153) and their movement can be controlled by magnets in the chip 100 or system 300. For example, the sample droplet 110 may be brought to the magnetic microbeads 153 (or the microbeads 153 brought to the sample droplet 110) to drive a reaction. The sample droplet 110 may subsequently move while the magnetic microbeads 153 stay under the influence of the magnet. Alternatively, the magnet may, in some embodiments, move the magnetic microbeads 153 from the sample droplet 110. The magnet may be part of the analyzer 300 in a specific position to hold the paramagnetic microbeads 153 at certain DMF electrode 106 locations.

[0173] The use of filtration sites 151 and / or microbeads 153 within the chip 100 offers a relatively straightforward means to filter droplets 110. Multiple cutters 150, filtration sites 151 , and microbeads 153 can be provided on the chip 100 to ensure that subsequent droplets 110 are not contaminated by prior sample filtration. Furthermore, different types of cutters 150, filtration sites 151 , and microbeads 153 may be provided on the chip 100 to carry out, for example, different analyses.

[0174] Virtual digital microfluidic reservoirs.

[0175] As shown in FIG. 5A, some embodiments of the chip 100 include a specialized DMF reservoir 102 and a movement grid 104 made up of a plurality of DMF electrodes 106. Specialized DMF reservoirs 102 may be simple to operate and / or manufacture.

[0176] In some embodiments these reservoir electrodes 102 can be emulated using a number of individual standard grid electrodes 106 (e.g., DMF electrodes 106). Given the high-fidelity capacitance-based volume sensing method, individual DMF electrodes 144 (a subset of the DMF electrodes 106) can be used to create one or more virtual reservoirs 142 depending on the input sample volume. The geometry (e.g., the actuated electrodes 144) of such a virtual reservoir 142 can be adjusted in real-time based on the measured sample volume. Such a virtual reservoir 142 may be reconfigurable and transferable on the movement grid 104, which may lead to increased dispensing throughput and fault-tolerance. These virtual reservoirs 142 can improve sample droplet 110 dispensation at lower volumes because the virtual reservoir 142 can be dynamically adjusted. Furthermore, virtual reservoirs 142 can avoid catastrophic failure because they can provide multiple exit points and thus avoid failure at a single exit point.

[0177] FIG. 15A illustrates a dedicated reservoir electrode 102, according to some embodiments. A dedicated reservoir electrode 102 (that is to say one with a specified location and electrode associated with it on the chip 100) can provide a robust and straightforward way to hold and dispense sample.

[0178] FIG. 15B illustrates a virtual reservoir 142 made up of individual DMF electrodes 144, according to some embodiments.

[0179] Certain fixed reservoir designs have large electrodes to handle bulk volumes, however if the sample volume is not enough to overflow the single large electrode, aliquoting may not be possible because the volume is trapped on the large electrode. Alternatively, if the volume ofsample overflows the bounds of the electrode and the dedicated cutting electrodes adjacent to the large electrode, aliquoting may again not be possible because the entire area is filled with liquid. A virtual reservoir 142 can split the single large electrode into many reconfigurable smaller electrodes 144, which can adapt as required to properly aliquot sample droplets 110. In the case of smaller volume input where the volume is too small for a single large electrode, having multiple smaller electrodes 144 avoids trapping the sample droplets 110 on a single large electrode. If a larger volume is input to the chip 100 (up to a limit), adjacent electrodes 106 to the sample area can be repurposed for aliquoting.

[0180] A virtual reservoir 142 may be composed of multiple DMF electrodes 144. The virtual reservoir 142 may provide the C-shaped reservoir configuration similar to that of reservoir electrode 102. In some embodiments, the virtual reservoir 142 may take other shapes (see for example the virtual reservoir of FIG. 5B). In some embodiments, the DMF electrodes 144 may be configured to use capacitive feedback from the droplets 110 to guide droplets 110. Such capacitive feedback can monitor and adjust (e.g., in real-time) the dispensing operations. Such a virtual reservoir 142 may have multiple paths for droplet 110 dispensations to provide operational redundancy. Multiple paths may additionally reduce the impact of biofouling of the original pathway.

[0181] The virtual reservoir 142 can allow dispensing in cases where fixed reservoir designs may fail (e.g., if there's either too much liquid or too little liquid). The use of the virtual reservoir 142 can make the chip 100 more tolerant to a wider range of input sample volumes. This can permit imprecise sample volume which may make the chip 100 usable by unskilled users.

[0182] Real-time DMF EWOD dielectric breakdown detection.

[0183] In some cases, due to fabrication imperfections or voltage overload, the dielectric component of a double-plate EWOD device can breakdown, creating a short-circuit between the high-voltage electrodes and the droplet 110. This can cause fluid electrolysis and can generate unintended chemical products (e.g., hydrogen and oxygen gas in the case of water). This can restrict sample droplet 110 movements and invalidate any results.

[0184] In some embodiments, a fuse placed in series with the high-voltage electrode(s) may be used to detect dielectric breakdown. Such detector configurations necessitate additional hardware cost and require manual repair if the fuse is tripped.

[0185] In some preferable embodiments where the top plate of the chip 100 is floating, (e.g., it is not grounded electrically and instead allowed to be at a voltage based on electrical circuit conditions; like in the presence of a high-fidelity capacitance-based volume detection method), distortion of the floating top-plate waveform can be used to deduce the presence of a shorted DMF electrode 106 in contact with the droplet 110. By testing each actuated electrode 106 in turn, the faulty electrode(s) 106 can be identified and avoided. This may permit operation to continue under certain circumstances. Such solutions can be implemented in software without requiring additional hardware because it exploits existing feedback detection circuits. In some embodiments, the DMF electrodes 106 can be tested on a periodic basis. In some embodiments, the DMF electrodes 106 can be tested based on what is occuring at the DMF electrode 106.

[0186] FIG. 16 is a block diagram 1600 of a dielectric breakdown detector configuration, according to some embodiments.

[0187] FIG. 16 provides a functional diagram 1600 of the feedback starting at block 1610. HV pulses are applied to the EWOD device which has a floating ground top plate. Because it is floating, a capacitance build up can be created across the plates and have its size measured over time. The capacitance, or lack thereof, will highlight a breakdown.

[0188] The dielectric breakdown detection 1602 described herein can be implemented using the output signal of capacitive feedback system 1604.

[0189] During normal operation, the capacitive feedback signal output is an AC waveform with known DC offset voltage. When dielectric breakdown occurs, the DC offset changes significantly from the usual offset voltage, providing a criterion for the breakdown detection system to distinguish between normal operating conditions and breakdown. Other methods for distinguishing between normal operating conditions and breakdown may also be used. As such, the system may send an HV actuation waveform 1610 through each of the DMF electrodes 106 (or a select few based on, for example, a location of anomalous droplet 110 behaviour). This may test the DMF electrodes 106 that make up the double-plate EWOD device 1608 (e.g., chip 100). The response in the floating top plate 1606 will produce a measurable difference from the expected result which can be detected by the capacitive feedback system 1604. This difference can produce a dielectric breakdown detection 1602 which may have the system modify its digital microfluidic operations sequence (to avoid location of dielectric breakdown) or may raise an error alert. In some capacitive feedback circuits, the DC offset can return to its normal position when the electrode 106 where the breakdownhas taken place is switched off. This means that the detection system can deduce where the dielectric breakdown has occurred and use that information to inform subsequent microfluidic operations. For example, that information can be used by a microfluidic operation scheduling algorithm to reroute droplet 110 operations around the electrode 106 where dielectric breakdown has occurred.

[0190] Such dielectric breakdown systems may be implemented in devices under program control (e.g., requiring a microcontroller). The microcontroller can act based on a received signal. Shutdown is thereby slower and less reliable than if a hardware component such as a fuse was employed.

[0191] Dielectric breakdowns can cause the electronics to fail so being able to detect such and remove the faulty electrode area from use can save the test assay and potentially the device itself.

[0192] Spray on - Wipe off method to add dielectric to gaps between DMF electrodes.

[0193] There may be gaps between one or more pairs of DMF electrodes 106 (e.g., the black lines between DMF electrodes 106 in FIG. 6). These gaps may be manufactured by design to isolate the DMF electrodes 106 from one another. These gaps are generally very small and might allow an electric spark from one DMF electrode 106 to the next DMF electrode 106 given a high enough voltage. The dielectric strength of air in these gaps may be insufficient to prevent discharge when at high voltages.

[0194] In some embodiments, the gaps between DMF electrodes 106 can be filled. Filling these gaps can increase the dielectric strength of the gaps between the DMF electrodes 106 which can improve the range of operating voltages that can be used to move droplets. It can also reduce the likelihood of a electric spark between DMF electrodes 106.

[0195] In some embodiments, the gaps can be filled with a liquid that has a high dielectric strength. This cured liquid may act as the bottom layer dielectric described above (i.e. dielectric layer 114). This dielectric may be cured in place by LIV light or heat or covered by the dielectric to prevent leakage. In some embodiments, methods can be used to control the thickness of the liquid such as spin coating, dip coating, razor, or similar. In some embodiments, a liquid solution such as PDMS is used to fill the gaps.

[0196] In some embodiments, solid filling such as microbeads or fine particulate with a high dielectric strength can be used to fill the gaps between DMF electrodes 106 and reduce thelikelihood of dielectric breakdown. Microbeads or fine particulates may be mixed into a rapidly evaporating solvent such as, for example, acetone and can be sprayed onto the movement grid 104 and allowed to dry. The residue can then be wiped off using, for example, a mechanical method such as wipe or squeegee such that the gaps between DMF electrodes 106 at a lower elevation than the flat plane accumulate these beads / particles. The beads / particulates chosen can have a high dielectric strength and their presence in the gap greatly increases the dielectric strength of the medium between two electrodes 106. Use of a rapidly evaporating solvent may avoid using liquid solutions whose liquid surface tension can affect the filling of gaps resulting in sections that are not fully occupied. Additionally, this may simplify the process by obviating any additional steps that need to be carried out to solidify the liquid prior to further manufacturing.

[0197] One method of implementation uses the top coat of NeverWet (e.g., a commercially available hydrophobic surface coating) that consists of dimethyl silicone polymer with silica in acetone. This can be allowed to dry and the excess wiped off using acetone to leave behind the beads in the gaps between electrodes 106.

[0198] In some embodiments, the microbeads or fine particulates may be applied by spreading the microbeads or fine particulates directly with a distribution means such as a piece of foam or silicone and wiping excess particulates off the movement grid 104. Applying the microbeads or fine particulates as a powder may prevent them from aggregating (as may happen in a solvent) and puncturing the dielectric layer 114.

[0199] DMF EWOD electrode height alignment with PCB substrate on a cavity PCB.

[0200] Precise control of DMF electrode 106 heights on PCB substrates may be important. Pinning can be caused by contaminants on the surface or buildup of proteins falling out of solution or by the shape or smoothness of the surface. Gaps between the DMF electrodes 106 may also cause pinning due to their depth and / or width. Instead of being constrained in a 2D plane (the PCB surface), DMF electrodes 106 can be either raised or lowered relative to the PCB substrate. In some configurations, with DMF electrodes 106 raised above the PCB surface, there can be a risk of droplet 110 edge pinning while moving off of the DMF electrode 106. Whenever materials are added to the surface of the base plate, plateaus or mountains may be created. For example, the gold electrode deposited on the surface may be 50 pm high which may cause a gap or valley between the DMF electrodes 106 to be 50 pm which may in turn cause pinning. EWOD forces are small and may not be able to push / pull a droplet through the valley.

[0201] In some embodiments, to avoid the above challenge, the DMF electrodes 106 can be lowered slightly below the PCB 112 surface or placed inline with the surface.

[0202] Sample droplet 110 transfer between adjacent microfluidic sub-chips on a single microfluidic device (chip 100) is often useful (e.g. transfer from DMF electrode 106 to DMF electrode 106 and transfer from DMF electrodes 106 to electrochemical sensor 108). Conventional two-layer printed circuit boards used for DMF have DMF electrodes 106 raised slightly above the PCB substrate, which can lead to droplet 110 edge pinning and / or dielectric uniformity issues during application. A combination of judicious PCB layer thickness selection and PCB copper weight combined with appropriate PCB cavities can reduce the height difference between DMF electrodes 106 and the surrounding substrate, improving fabrication quality, once any gaps between the substrate and electrodes are filled in.

[0203] EWOD reservoir dispensing reliability enhancement using PCB cavities.

[0204] FIG. 17A shows a plan view of the chip 100 indicating the separation walls and FIG. 17B shows a perspective view of the chip 100 from FIG. 17A.

[0205] Separation walls 160 can increase reservoir 102 dispensing reliability. By using cavity PCB manufacturing processes, the separation wall 160 (sometimes a separate component affixed to the PCB 112) can be combined with the PCB 112 itself. DMF separation walls 160 may be built by placing partition layers on top of the DMF surface, which adds a manufacturing step which may be subject to placement or adhesion issues. Multiple layers of solder mask might also be used for this purpose, but solder mask application is usually a manual process and solder mask height is uncontrolled, leading to reproducibility issues.

[0206] A separation wall 160 around DMF reservoir dispensing electrodes 102 can be created using a cavity PCB with the DMF electrodes 102 inset into the PCB 112 surface. The separation wall 160 may then be part of the chip 100 itself instead of being a separate component affixed to the chip 100 surface. The separation wall 160 may comprise a physical wall that may be configured to be hydrophobic. The separation wall 160 may act as a guide for dispensing through the desired exit.

[0207] In some embodiments, EWOD reservoir 102 dispensing reliability can be improved by the presence of a separating wall (with a gap) to enforce the electrodes’ boundary geometry. Separation walls can be conventionally built by placing partition layers on top of the DMF surface,which adds a manufacturing step which may be subject to placement or adhesion issues. Printed circuit board assemblies used in DMF can have a uniform substrate and electrode thickness (wherein the electrode height is slightly more than that of the substrate). In contrast, cavity PCBs, common to radio-frequency applications, can contain board cut-outs, allowing for the integration of a separation wall as part of the board itself, by having the DMF electrodes set below the PCB's 112 top surface in a cavity.

[0208] Example Implementations.

[0209] In one aspect, the disclosure describes a device for sample analysis. The device includes a movement grid 104 including a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126. A plurality of digital microfluidic (DMF) electrodes 106 are configured to selectively actuate regions of the dielectric layer 114 to move a sample droplet 110 within the cavity 126 between regions corresponding to each of the plurality of DMF electrodes 106 via electrowetting-on-dielectric forces. The device also includes at least one sensor 108 configured to measure the sample droplet 110, at least one filtration site 151 corresponding to at least one filtration DMF electrode 106 of the plurality of DMF electrodes 106. The device is configured to move the sample droplet 110 into the filtration site 151 by the plurality of DMF electrodes 106 and move the sample droplet 110 out of the filtration site 151 by the plurality of DMF electrodes 106. The device is configured to move the sample droplet 110 in the movement grid 104 through the at least one filtration site 151 to the at least one sensor 108.

[0210] In some embodiments, the device is configured to move the sample droplet 110 from a first neighbouring region corresponding to at least one first neighbouring DMF electrode 106 of the plurality of DMF electrodes 106 into the at least one filtration site 151 and from the filtration site 151 to a second neighbouring region corresponding to at least one second neighbouring DMF electrode 106 of the plurality of DMF electrodes 106.

[0211] In some embodiments, the filtration site 151 includes at least one of a filter material 152 functionalized for specific protein removal, a filter 152 to assist with the precipitation of unwanted substances, a prefabricated filter 152, and a polymer matrix.

[0212] In some embodiments, the filter material 152 functionalized for specific protein removal comprises biotin / avidin complexes or antibody / aptamer specific targeting.

[0213] In some embodiments, the filter 152 to assist with the precipitation of unwanted substances comprises dextran.

[0214] In some embodiments, the filtration site 151 is held in place by at least one of doublesided tape or friction between the top layer and the bottom layer.

[0215] In some embodiments, edges 154 of the filtration site 151 through which no sample droplet 110 is configured to travel are sealed using a barrier.

[0216] In some embodiments, the barrier is at least one of a hydrophobic barrier, a solid barrier, double-sided tape, and a hydrophobic solution deposited along the edges of the filter 152.

[0217] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid 104 including a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126. A plurality of digital microfluidic (DMF) electrodes 106 are configured to selectively actuate regions of the dielectric layer 114 to move a sample droplet 110 within the cavity 126 between regions corresponding to each of the plurality of DMF electrodes 106 via electrowetting-on-dielectric forces. The device also includes at least one sensor 108 configured to measure the sample droplet 110, and microbeads 153 to trap specific components or to remove precipitated components from the sample droplet 110. The device is configured to expose the sample droplet 110 to the microbeads 153 and move the sample droplet 110 in the movement grid 104 to the at least one sensor 108.

[0218] In some embodiments, the device further includes a filtration site 151 to filter the microbeads 153 from the sample droplet 110.

[0219] In some embodiments, the microbeads 153 are magnetic microbeads 153, and the device further includes a magnet configured to separate the magnetic microbeads 153 and the sample droplet 110 after exposing the sample droplet 110 to the magnetic microbeads 153.

[0220] According to a further aspect, there is provided a device for sample analysis. The device includes a sample inlet to receive a sample, and a movement grid 104 comprising a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126. A plurality of digital microfluidic (DMF)electrodes 106 are configured to selectively actuate regions of the dielectric layer 114 to move a sample droplet 110 within the cavity 126 between regions corresponding to each of the plurality of DMF electrodes 106 via electrowetting-on-dielectric forces. The device also includes at least one sensor 108 configured to analyze a sample droplet 110. The device is configured to move the sample droplet 110 through the movement grid 104 and to the at least one sensor 108. A subset of the plurality of DMF electrodes 144 are configured to act as a reservoir electrode 142 capable of dispensing the sample droplet 110 from at least some of the sample.

[0221] In some embodiments, the subset of the plurality of DMF electrodes 144 control sample droplet 110 dispensation based in part on high-fidelity capacitance-based volume sensing.

[0222] In some embodiments, the device can adjust geometry of the reservoir electrode 142 based in part on high-fidelity capacitance-based volume sensing.

[0223] In some embodiments, the subset of the plurality of DMF electrodes 144 is reconfigurable.

[0224] In some embodiments, the reservoir electrode 142 is transferable to another subset of the plurality of DMF electrodes 144.

[0225] According to a further aspect, there is provided a device for sample analysis. The device includes a sample inlet to receive a sample and provide the sample with hydrophilic contact with transfer paper 140, and a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126 containing the transfer paper 140. At least one electrode 102 is configured to selectively actuate the dielectric layer 114 and move the sample via electrowetting-on-dielectric forces. When the sample is provided, the sample contacts the transfer paper 140 and is brought into contact with the top layer and the bottom layer establishing electrical contact with the at least one electrode 102, and the at least one electrode 102 is actuated to draw the sample out of the transfer paper 140.

[0226] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid 104 including a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126. A plurality of digital microfluidic (DMF) electrodes 106 are configured toselectively actuate regions of the dielectric layer 114 to move a sample droplet 110 within the cavity 126 between regions corresponding to each of the plurality of DMF electrodes 106 by electrowetting-on-dielectric forces. The device also includes at least one sensor 108 configured to measure the sample droplet 110. Breakdown of the dielectric layer 114 corresponding to at least one broken DMF electrode 106 of the plurality of DMF electrodes 106 is detected. The device is configured to move the sample droplet 110 through the movement grid 104 and to the at least one sensor 108 by avoiding the at least one broken DMF electrode 106.

[0227] According to a further aspect, there is provided a device for sample analysis. The device includes a movement grid 104 including a top layer and a bottom layer. The bottom layer includes a dielectric layer 114 coated with a bottom hydrophobic layer 118. The top layer includes a conductive top plate 120 coated with a top hydrophobic layer 119. The top layer and the bottom layer define a cavity 126. A plurality of digital microfluidic (DMF) electrodes 106 are configured to selectively actuate regions of the dielectric layer 114 to move a sample droplet 110 within the cavity 126 between regions corresponding to each of the plurality of DMF electrodes 106 via electrowetting-on-dielectric forces. The device also includes at least one sensor 108 configured to measure the sample droplet 110. The device is configured to move the sample droplet 110 through the movement grid 104 and to the at least one sensor 108.

[0228] In some embodiments, at least some gaps between the DMF electrodes 106 are filled with microbeads or fine particulates having high dielectric strength.

[0229] In some embodiments, the microbeads or fine particulates are applied by mixing the microbeads or fine particulates into an evaporating solvent, spraying said mixture onto the movement grid, and wiping excess of the mixture off the movement grid 104.

[0230] In some embodiments, the microbeads or fine particulates are applied by spreading the microbeads or fine particulates, and wiping excess of the mixture off the movement grid 104.

[0231] In some embodiments, the height of adjacent DMF electrodes 106 are aligned.

[0232] In some embodiments, the device further includes a reservoir including a top reservoir layer and a bottom reservoir layer. The bottom reservoir layer includes a dielectric reservoir layer 114 coated with a bottom hydrophobic reservoir layer 118. The top reservoir layer includes a conductive reservoir top plate 120 coated with a top hydrophobic reservoir layer 119. The top reservoir layer and the bottom reservoir layer define a cavity 126. A reservoir digital microfluidicelectrode 102 is configured to selectively actuate the reservoir to dispense the sample droplet 110 to the movement grid 104 via electrowetting-on-dielectric forces. The reservoir is defined in part by an integral separation wall 160.

[0233] Computer Implementation Details.

[0234] The embodiments of the devices, systems and methods described herein may be implemented in a combination of both hardware and software. These embodiments may be implemented on programmable computers, each computer including at least one processor, a data storage system (including volatile memory or non-volatile memory or other data storage elements or a combination thereof), and at least one communication interface.

[0235] Program code is applied to input data to perform the functions described herein and to generate output information. The output information is applied to one or more output devices. In some embodiments, the communication interface may be a network communication interface. In embodiments in which elements may be combined, the communication interface may be a software communication interface, such as those for inter-process communication. In still other embodiments, there may be a combination of communication interfaces implemented as hardware, software, and combination thereof.

[0236] Throughout the foregoing discussion, numerous references will be made regarding servers, services, interfaces, portals, platforms, or other systems formed from computing devices. It should be appreciated that the use of such terms is deemed to represent one or more computing devices having at least one processor configured to execute software instructions stored on a computer readable tangible, non-transitory medium. For example, a server can include one or more computers operating as a web server, database server, or other type of computer server in a manner to fulfill described roles, responsibilities, or functions.

[0237] The technical solution of embodiments may be in the form of a software product. The software product may be stored in a non-volatile or non-transitory storage medium, which can be a compact disk read-only memory (CD-ROM), a USB flash disk, or a removable hard disk. In some embodiments, the software product may be stored on an EEPROM on the chip 100 which can communicate with a processor on board the analyzer 300. The software product includes a number of instructions that enable a computer device (personal computer, server, or network device) to execute the methods provided by the embodiments.

[0238] The embodiments described herein are implemented by physical computer hardware, including computing devices, servers, receivers, transmitters, processors, memory, displays, and networks. The embodiments described herein provide useful physical machines and particularly configured computer hardware arrangements. The embodiments described herein are directed to electronic machines and methods implemented by electronic machines adapted for processing and transforming electromagnetic signals which represent various types of information. The embodiments described herein pervasively and integrally relate to machines, and their uses; and the embodiments described herein have no meaning or practical applicability outside their use with computer hardware, machines, and various hardware components. Substituting the physical hardware particularly configured to implement various acts for non-physical hardware, using mental steps for example, may substantially affect the way the embodiments work. Such computer hardware limitations are clearly essential elements of the embodiments described herein, and they cannot be omitted or substituted for mental means without having a material effect on the operation and structure of the embodiments described herein. The computer hardware is essential to implement the various embodiments described herein and is not merely used to perform steps expeditiously and in an efficient manner.

[0239] FIG. 18 is a schematic diagram of a computing device 1800, according to some embodiments. As depicted, computing device 1800 includes at least one processor 1802, memory 1804, at least one I / O interface 1806, and at least one network interface 1808. The computing device 1800 and aspect thereof may be provided within the user device 200 and the analyzer system 300 of FIG. 2.

[0240] For example, and without limitation, the computing device 1800 may be a server, network appliance, set-top box, embedded device, computer expansion module, personal computer, laptop, personal data assistant, cellular telephone, smartphone device, LIMPC tablets, video display terminal, gaming console, electronic reading device, and wireless hypermedia device or any other computing device capable of being configured to carry out the methods described herein.

[0241] For simplicity only one computing device 1800 is shown but system may include more computing devices 1800 operable by users to access remote network resources and exchange data. The computing devices 1800 may be the same or different types of devices. The computing device 1800 at least one processor, a data storage device (including volatile memory or non-volatile memory or other data storage elements or a combination thereof), and at least one communicationinterface. The computing device components may be connected in various ways including directly coupled, indirectly coupled via a network, and distributed over a wide geographic area and connected via a network (which may be referred to as “cloud computing”).

[0242] Each processor 1802 may be, for example, any type of general-purpose microprocessor or microcontroller, a digital signal processing (DSP) processor, an integrated circuit, a field programmable gate array (FPGA), a reconfigurable processor, a programmable read-only memory (PROM), or any combination thereof.

[0243] Memory 1804 may include a suitable combination of any type of computer memory that is located either internally or externally such as, for example, random-access memory (RAM), readonly memory (ROM), compact disc read-only memory (CDROM), electro-optical memory, magneto-optical memory, erasable programmable read-only memory (EPROM), and electrically- erasable programmable read-only memory (EEPROM), Ferroelectric RAM (FRAM) or the like.

[0244] Each I / O interface 1806 enables computing device 1800 to interconnect with one or more input devices, such as a keyboard, mouse, camera, touch screen and a microphone, or with one or more output devices such as a display screen and a speaker.

[0245] Each network interface 1808 enables computing device 1800 to communicate with other components, to exchange data with other components, to access and connect to network resources, to serve applications, and perform other computing applications by connecting to a network (or multiple networks) capable of carrying data including the Internet, Ethernet, plain old telephone service (POTS) line, public switch telephone network (PSTN), integrated services digital network (ISDN), digital subscriber line (DSL), coaxial cable, fiber optics, satellite, mobile, wireless (e.g. Wi-Fi, WiMAX), SS7 signaling network, fixed line, local area network, wide area network, and others, including any combination of these.

[0246] Computing device 1800 is operable to register and authenticate users (using a login, unique identifier, and password for example) prior to providing access to applications, a local network, network resources, other networks and network security devices. Computing devices 1800 may serve one user or multiple users.

[0247] Implementation Details.

[0248] The following discussion provides many example embodiments. Although each embodiment represents a single combination of inventive elements, other examples may includeall possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, other remaining combinations of A, B, C, or D, may also be used.

[0249] Although terms such as “maximize”, “minimize” and “optimize” may be used in the present disclosure, it should be understood that such term may be used to refer to improvements, tuning and refinements which may not be strictly limited to maximal, minimal or optimal.

[0250] The term “connected” or "coupled to" may include both direct coupling (in which two elements that are coupled to each other contact each other) and indirect coupling (in which at least one additional element is located between the two elements).

[0251] The term “substantially” as used herein may be applied to modify any quantitative representation which could permissibly vary without resulting in a change in the basic function to which it is related. For example, a drive shaft as disclosed herein having a circular transverse crosssection may permissibly have a somewhat non-circular cross-section within the scope of the invention if its rotational driving capability is not materially altered.

[0252] Although the embodiments have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope as defined by the appended claims.

[0253] Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

[0254] As can be understood, the examples described above and illustrated are intended to be exemplary only. The scope is indicated by the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A device for sample analysis, the device comprising: a movement grid comprising a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive top plate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity, wherein a plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces; at least one sensor configured to measure the sample droplet; at least one filtration site corresponding to at least one filtration DMF electrode of the plurality of DMF electrodes, wherein the device is configured to move the sample droplet into the filtration site by the plurality of DMF electrodes and move the sample droplet out of the filtration site by the plurality of DMF electrodes; wherein the device is configured to move the sample droplet in the movement grid through the at least one filtration site to the at least one sensor.2 The device of claim 1 , wherein the device is configured to move the sample droplet from a first neighbouring region corresponding to at least one first neighbouring DMF electrode of the plurality of DMF electrodes into the at least one filtration site and from the filtration site to a second neighbouring region corresponding to at least one second neighbouring DMF electrode of the plurality of DMF electrodes.3 The device of claim 1 , wherein the filtration site comprises at least one of a filter material functionalized for specific protein removal, a filter to assist with the precipitation of unwanted substances, a prefabricated filter, and a polymer matrix.4 The device of claim 3, wherein the filter material functionalized for specific protein removal comprises biotin / avidin complexes or antibody / aptamer specific targeting.5 The device of claim 3, wherein the filter to assist with the precipitation of unwanted substances comprises dextran.

6. The device of claim 1 , wherein the filtration site is held in place by at least one of doublesided tape or friction between the top layer and the bottom layer.

7. The device of claim 1 , wherein edges of the filtration site through which no sample droplet is configured to travel are sealed using a barrier.8 The device of claim 7, wherein the barrier is at least one of a hydrophobic barrier, a solid barrier, double-sided tape, and a hydrophobic solution deposited along the edges of the filter.9 A device for sample analysis, the device comprising: a movement grid comprising a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive top plate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity, wherein a plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces; at least one sensor configured to measure the sample droplet; microbeads to trap specific components or to remove precipitated components from the sample droplet; wherein the device is configured to expose the sample droplet to the microbeads and move the sample droplet in the movement grid to the at least one sensor.10 The device of claim 9, further comprising a filtration site to filter the microbeads from the sample droplet.11 The device of claim 9, wherein the microbeads are magnetic microbeads, and the device further comprises a magnet configured to separate the magnetic microbeads and the sample droplet after exposing the sample droplet to the magnetic microbeads.12 A device for sample analysis, the device comprising: a sample inlet to receive a sample; a movement grid comprising a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive topplate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity, wherein a plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces; at least one sensor configured to analyze the sample droplet; wherein the device is configured to move the sample droplet through the movement grid and to the at least one sensor; wherein a subset of the plurality of DMF electrodes are configured to act as a reservoir electrode capable of dispensing the sample droplet from at least some of the sample.

13. The device of claim 12, wherein the subset of the plurality of DMF electrodes control sample droplet dispensation based in part on high-fidelity capacitance-based volume sensing.

14. The device of claim 12, wherein the device can adjust geometry of the reservoir electrode based in part on high-fidelity capacitance-based volume sensing.

15. The device of claim 12, wherein the subset of the plurality of DMF electrodes is reconfigurable.

16. The device of claim 12, wherein the reservoir electrode is transferable to another subset of the plurality of DMF electrodes.

17. A device for sample analysis, the device comprising: a sample inlet to receive a sample and provide the sample with hydrophilic contact with transfer paper; a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive top plate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity containing the transfer paper, wherein at least one electrode is configured to selectively actuate the dielectric layer and move the sample via electrowetting-on-dielectric forces; wherein when the sample is provided, the sample contacts the transfer paper and is brought into contact with the top layer and the bottom layer establishing electrical contact with the at leastone electrode, and the at least one electrode is actuated to draw the sample out of the transfer paper.

18. A device for sample analysis, the device comprising: a movement grid comprising a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive top plate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity, wherein a plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes by electrowetting-on-dielectric forces; at least one sensor configured to measure the sample droplet; wherein breakdown of the dielectric layer corresponding to at least one broken DMF electrode of the plurality of DMF electrodes is detected; wherein the device is configured to move the sample droplet through the movement grid and to the at least one sensor by avoiding the at least one broken DMF electrode.

19. A device for sample analysis, the device comprising: a movement grid comprising a top layer and a bottom layer, the bottom layer comprising a dielectric layer coated with a bottom hydrophobic layer, the top layer comprising a conductive top plate coated with a top hydrophobic layer, the top layer and the bottom layer defining a cavity, wherein a plurality of digital microfluidic (DMF) electrodes are configured to selectively actuate regions of the dielectric layer to move a sample droplet within the cavity between regions corresponding to each of the plurality of DMF electrodes via electrowetting-on-dielectric forces; at least one sensor configured to measure the sample droplet; wherein the device is configured to move the sample droplet through the movement grid and to the at least one sensor.

20. The device of claim 19, wherein at least some gaps between the DMF electrodes are filled with microbeads or fine particulates having high dielectric strength.

21. The device of claim 20, wherein the microbeads or fine particulates are applied by:mixing the microbeads or fine particulates into an evaporating solvent, spraying said mixture onto the movement grid, and wiping excess of the mixture off the movement grid.

22. The device of claim 20, wherein the microbeads or fine particulates are applied by: spreading the microbeads or fine particulates, and wiping excess of the mixture off the movement grid.

23. The device of claim 20, wherein the height of adjacent DMF electrodes are aligned.

24. The device of claim 20, further comprising a reservoir comprising a top reservoir layer and a bottom reservoir layer, the bottom reservoir layer comprising a dielectric reservoir layer coated with a bottom hydrophobic reservoir layer, the top reservoir layer comprising a conductive reservoir top plate coated with a top hydrophobic reservoir layer, the top reservoir layer and the bottom reservoir layer defining a cavity, wherein a reservoir digital microfluidic electrode is configured to selectively actuate the reservoir to dispense the sample droplet to the movement grid via electrowetting-on-dielectric forces; wherein the reservoir is defined in part by an integral separation wall.

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