Method of electrowetting
Inventors
Chen, Michael Chun Hao • Kalsi, Sumit • Bell, Laurence Livingstone • Mcinroy, Gordon Ross • ZHITOMIRSKY, David • Slominski, Luke M. • Paolini, Jr., Richard J. • Visani, Cristina
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Assignees
Member
NucleraNuclera develops automated benchtop platforms and integrated systems for rapid protein expression, optimization, and purification, utilizing cell-free synthesis, digital microfluidics, and software-driven workflows. Their technology enables miniaturized and scalable protein prototyping—including challenging targets such as membrane proteins—directly at the lab bench. Nuclera serves academic and industrial researchers, focusing on reducing turnaround time for functional protein access and streamlining screening and production. The company has secured significant funding to enable broad commercialization, expanded their leadership team to support scale-up, and continues to drive advancements in drug discovery, proteomics, and experimental automation.
Nuclera develops automated benchtop platforms and integrated systems for rapid protein expression, optimization, and purification, utilizing cell-free synthesis, digital microfluidics, and software-driven workflows. Their technology enables miniaturized and scalable protein prototyping—including challenging targets such as membrane proteins—directly at the lab bench. Nuclera serves academic and industrial researchers, focusing on reducing turnaround time for functional protein access and streamlining screening and production. The company has secured significant funding to enable broad commercialization, expanded their leadership team to support scale-up, and continues to drive advancements in drug discovery, proteomics, and experimental automation.
Publication Number
US-11806715-B2
Publication Date
2023-11-07
Expiration Date
Abstract
A method for moving an aqueous droplet comprising providing an electrokinetic device including a first substrate having a matrix of electrodes, wherein each of the matrix electrodes is coupled to a thin film transistor, and wherein the matrix electrodes are overcoated with a functional coating comprising: a dielectric layer in contact with the matrix electrodes, a conformal layer in contact with the dielectric layer, and a hydrophobic layer in contact with the confornial layer; a second substrate comprising a top electrode; a spacer disposed between the first substrate and the second substrate and defining an electrokinetic workspace; and a voltage source operatively coupled to the niatrix electrodes. The method further comprises disposing an aqueous droplet on a first matrix electrode; and providing a differential electrical potential between the first matrix electrode and a second matrix electrode with the voltage source, thereby moving the aqueous droplet.
Core Innovation
The invention provides a method for moving an aqueous droplet using an electrokinetic device comprising a first substrate having a matrix of electrodes each coupled to a thin film transistor, the matrix electrodes overcoated with a functional coating comprising a dielectric layer in contact with the matrix electrodes, a conformal layer in contact with the dielectric layer, and a hydrophobic layer in contact with the conformal layer; a second substrate comprising a top electrode; a spacer defining an electrokinetic workspace; and a voltage source operatively coupled to the matrix electrodes. The method comprises disposing an aqueous droplet on a first matrix electrode and providing a differential electrical potential between the first matrix electrode and a second matrix electrode with the voltage source, thereby moving the aqueous droplet.
The background identifies contact angle saturation and hysteresis during electrowetting-on-dielectric (EWoD) operations as problems to be solved, arising from phenomena including entrapment of charges in the hydrophobic film or insulator/dielectric interface, adsorption of ions, dielectric breakdown, double layer capacitance effects, pinholes that permit electrolysis, ion permeation altering dielectric properties or surface potential, and surface fouling, all of which reduce operational lifetime and inhibit droplet actuation.
The inventors found that contact angle hysteresis arising from high conductivity solutions or solutions deviating from neutral pH can be mitigated by depositing a conformal layer, in particular a thin protective parylene coating between the insulating dielectric and the hydrophobic coating, thereby enabling robust actuation of high ionic strength solutions for extended periods and repeated droplet operations.
Claims Coverage
Coverage is based on one independent claim and seven main inventive features identified from that claim.
Matrix electrodes coupled to thin film transistors
A first substrate having a matrix of electrodes, wherein each of the matrix of electrodes is coupled to a thin film transistor.
Functional coating with dielectric, conformal and hydrophobic layers
The matrix of electrodes are overcoated with a functional coating comprising a dielectric in contact with the matrix of electrodes, a conformal layer comprising parylene in contact with the dielectric, and a hydrophobic layer in contact with the conformal layer.
Dielectric comprising aluminium oxide and hafnium oxide
A dielectric in contact with the matrix of electrodes, the dielectric comprising a layer of aluminium oxide and a layer of hafnium oxide.
Conformal parylene layer circa 100 nm thick
A conformal layer comprising parylene in contact with the dielectric, wherein the parylene is circa 100 nm in thickness.
Second substrate with top electrode and hydrophobic layer
A second substrate comprising a top electrode and a second hydrophobic layer.
Spacer defining electrokinetic workspace
A spacer disposed between the first substrate and the second substrate and defining an electrokinetic workspace.
Voltage source controllable to move aqueous droplet
A voltage source operatively coupled to the matrix of electrodes, the voltage source controllable to provide a differential electrical potential between a first matrix electrode and a second matrix electrode in order to move the aqueous droplet between the first matrix electrode and the second matrix electrode.
The independent claim covers an active matrix electrokinetic device combining TFT-coupled electrode arrays overcoated with a dielectric/parylene/hydrophobic stack, a second substrate with a top electrode, a spacer-defined workspace, and a controllable voltage source for differential actuation to move aqueous droplets.
Stated Advantages
Mitigates contact angle hysteresis arising from high conductivity solutions or solutions deviating from neutral pH.
Enables robust actuation of high ionic strength solutions for extended periods of time.
Prevents damage and defects to array elements contacted by high ionic strength droplets, preserving the ability of aqueous droplets to wet, dispense, split, and be moved.
Supports repeated droplet movement operations, including more than 1,000 or more than 10,000 repetitions and repeated operations within a 24-hour period.
Documented Applications
An assay, nucleic acid synthesis, nucleic acid assembly, nucleic acid amplification, nucleic acid manipulation, next-generation sequencing library preparation, protein synthesis, or cellular manipulation.
Moving cells, nucleic acids, nucleic acid templates, proteins, initiation oligonucleotide sequences for nucleic acid synthesis, beads, magnetic beads, cells immobilised on magnetic beads, or biopolymers immobilised on magnetic beads.
Enzymatic nucleic acid synthesis including terminal deoxynucleotidyl transferase (TdT) mediated addition of 3'-O-reversibly terminated nucleoside 5'-triphosphates and associated wash and deprotection steps that use high solute concentration solutions.
Preparation of contiguous oligonucleotide sequences by synthesis and assembly of immobilised initiation oligonucleotide sequences including selective cleavage, hybridization, and joining steps.
Cell-free protein expression in an oil-filled environment where droplets containing a nucleic acid template and a cell-free system are moved using the electrokinetic device.
Automation in a cartridge for local clinician diagnostics, including nucleic acid amplification testing (NAAT) for pathogen or virus detection and related sample preparation and library preparation for next generation sequencing.
Interested in licensing this patent?