Research Terms
Researchers at the University of Central Florida have developed a novel diagnostic kit for quickly identifying microorganisms and detecting live versus dead cells, based on their electrical activity. The invention can also be used to determine whether a cell is actively growing, drug-resistant or drug-susceptible. With such a comprehensive diagnostic tool, clinicians (plant pathologists, doctors and veterinarians) will be able to determine the stage of a disease and prescribe the most effective treatment strategy.
Compared to conventional testing methods, the invention is a significant improvement. Tests, such as Polymerase Chain Reaction (PCR), only enable clinicians to identify whether a pathogenic microorganism is present—not whether the cells are live or dead. Thus, the tests lack the ability to gauge the stage of a microorganism’s growth and how best to fight a disease. Moreover, the tests are often inefficient and slow at providing results (requiring hours or days for processing).
The invention is a diagnostic kit for quickly detecting the presence of different pathogenic microorganisms, their viability and metabolic states. The detection mechanism identifies differences in the electric signatures of cells, both on their surface and their immediate micro-environment. Cells of both pathogenic and non-pathogenic microorganisms (such as bacteria, fungi and viruses) exhibit electrical activity as they interact with their surroundings and exchange ions across cell walls.
Specifically, the kit comprises a method and apparatus to detect the electrochemical response of a microorganism and to compare that response against a database for identification. The apparatus of the invention includes an interdigitated electrode (IDE), which detects morphological changes, and/or a microelectrode array (MEA), which captures electrophysiological measurements.
In an example use, a clinician takes a sample from an infected orange tree and uses the diagnostic kit to generate an electrophysiological and/or impedance signature of the sample. The measurements are then compared with the electrophysiological and/or impedance signatures stored in the system’s memory. Based on the sample results, the system indicates that the tree is infected with the American form of Huanglongbing (HLB), a citrus disease caused by the bacterium, Candidatus Liberibacter americanus. The kit also enables the clinician to distinguish between live and dead cells in the sample and to determine the stage of growth.
The University of Central Florida invention describes a new device combining the simplicity of an interdigitated electrode (IDE) with the sophistication of plasmonics for in vitro biosensing applications. The nanoscale geometry of the polyacrylonitrile (PAN) plasmonic layer on a glass substrate is tuned to maximize the targeted interaction of this layer with electrodes and cells which is subsequently measured. Such an interaction could dramatically improve the sensitivity of IDEs enabling the plasmonic interdigitated electrodes (PIDEs) to be a new tool for the electrical and optical analysis of single cells and a network of cells. These devices may be used in applications such as in vitro drug development, single-cell analysis, toxicity testing and organ-on-a-chip models.
Researchers at the University of Central Florida have invented a new fabrication technology for 3D microelectrode arrays (MEAs) to stimulate and record electrophysiological activity from cellular networks in vitro. The novel technology enables manufacturers to produce 3D-printed MEAs with spin-coated insulation and functional electrospun 3D scaffolds. The culture-ready systems can be used as fully functional "disease in a dish" and "organ on a chip" to promote cell/tissue growth and regeneration.
MEA technology has been widely-used as a platform for recording and stimulating electrical activity in electrogenic cells such as neurons, cardiomyocytes, and pancreatic beta cells for both in vitro and in vivo applications. Since the tissue environment is essentially 3D, there is an increasing need to extend cell culture matrices, support scaffolds, and microelectrodes to 3D form factors, as well. Yet, today’s MEAs are predominantly made using microelectronics fabrication processes or complex glass-based approaches that restrict their functionality to 2D applications. For example, they are unable to capture electrophysiological signals that occur at a certain height when cell cultures mature and obtain a 3D form. Additionally, creating a suitable insulation layer for 3D electrodes has always remained a challenge, due to diverse topographies for conformal deposition of biocompatible materials with a low thermal budget.
The UCF technology resolves these issues and enables manufacturers to fabricate 3D MEAs that are not only superior to their 2D counterparts but are also simple to produce using 3D printing techniques. In addition, the 3D nanoscaffolding enables a functional layer for accurate cellular placement, tissue engineering and complex 3D culture architectures.
The invention consists of methods and techniques for producing electrospun polyethylene terephthalate (PET) 3D scaffolds coupled to fabricated MEAs. The microfabrication technology involves the creation of 3D towers via 3D printing and a metallization layer, defined by stencil mask evaporation techniques. Multiple insulation strategies can be used with the technology, including the following: a drop-casted/spin-coated 3D layer of polystyrene (PS) and an evaporated layer of SiO2, both of which are laser micromachined to produce the 3D microelectrodes.
"Fabrication and Characterization of 3D Printed, 3D Microelectrode Arrays with Spin Coated Insulation and Functional Electrospun 3D Scaffolds for 'Disease in a Dish' and 'Organ on a Chip' Models," Conference paper for the 18th Solid State Sensors, Actuators and Microsystems Workshop (Hilton Head 2018), Hilton Head, SC, June 2018.
Researchers at the University of Central Florida have developed a novel 4D biosensor for lab-on-a-chip and wearable sensor applications that is more cost-effective and easier to manufacture than current technologies. Made of dynamic, stretchable, packaged 3D-printed structures, the biosensor has shape-memory recovery. Additionally, its flexibility is tunable and can match biological materials (such as skin or brain tissue). The new biosensor design also enables the use of more complex 3D electrodes in extremely flexible and conformable structures. Thus, the device can maintain its electrical functions and return naturally to its resting state even when subjected to high strain caused by twisting, bending, stretching or compressive forces.
Technical Details
The UCF invention consists of a novel 4D biosensor device and microfabrication methods for creating the device. Stereolithographic (SLA) 3D printing can be used to quickly produce monolithic structures with high resolution and small feature sizes. The device may include a 3D-printed base serpentine structure, a polyimide packaging substrate, and elastomeric insulation. By accommodating the use of different resins and structural design changes, the invention enables manufacturers to tune the flexibility of the printed design to match biological materials such as skin and brain tissue.
The integration of 3D structures, LEDs, and helices followed by bending/twisting analysis depict the capability of the device to retain its resting-state conformation ""memory,"" giving it unique 4D characteristics. Microelectrode impedance (17.1kOhm at 1 kHz), and 85 percent and 200 percent strain measurements demonstrated the versatility of the invention. In an example application, the device comprises 3D-printed serpentine designs with various out-of-plane structures integrated onto a flexible Kapton(R) package with micromolded polydimethylsiloxane insulation.
Partnering Opportunity
The research team is looking for partners to develop the technology further for commercialization.
Stage of Development
Prototype available.
Researchers at the University of Central Florida have developed a simple, inexpensive solution for fabricating 3D metal microelectrode arrays (MEAs) and microneedle platforms. Compared to current technologies, the UCF makerspace technology overcomes issues such as brittleness, high expense, complexity, and unrepeatable processes. As a result, the invention offers cost- and time-saving steps to produce microelectrode platforms for multiple biosystem applications. Examples include lab-on-a-chip devices, disease modeling, pre-clinical drug discovery, and drug/therapeutic delivery systems. Also, 3D MEAs configured using the technology performed comparably to conventional 3D MEAs.
Technical Details
The UCF fabrication technology comprises methods and techniques for developing microelectrode platforms. Besides enabling faster microfabrication outside the cleanroom, the makerspace invention also provides a better way to transition 2D MEA structures to 3D. Microelectrodes are typically machined in 2D and then transitioned by hand to 3D. However, at meso- and micro-scale levels, the transition process can result in inconsistencies and unwanted variability. The UCF technology resolves the problem by providing a custom-fabricated Hypodermic Needle Array (Hypo-Rig) that performs the transition faster and with greater precision. The array also complements existing microfabrication and assembly techniques such as laser micromachining and micromilling.
Simple in its design, the technology uses inexpensive materials (such as printing resin, epoxy and hypodermic needles) and is scalable for high volume production. In one example use, the Hypo-Rig array successfully batch-transitioned steel MEA arrays and micromilled microneedle arrays from 1x2 to 19x20 conformation in 2D to a tight, near-vertical grouping in 3D in a single step. The Hypo-Rig can act as a standalone hollow mesoneedle or microneedle array for drug delivery applications.
In another example, the research team built a viable culturing and substrate-agnostic 3D metal MEA platform. The team used micro-stereolithographic (µSLA) 3D printing, laser micromachining, the Hypo-Rig assembly technique, and other standard microfabrication processes. In experimental results, the 70µm microelectrodes demonstrated an impedance of 45.4kOhms at 1 kHz, and the Hypo-Rig transition enabled a tight Gaussian distribution of 70-degree conversion angles.
Partnering Opportunity
The research team is looking for partners to develop the technology further for commercialization.
Stage of Development
Prototype available.
Facile, Packaging Substrate-Agnostic, Microfabrication and Assembly of Scalable 3D Metal Microelectrode Arrays for in Vitro Organ-on-a-Chip and Cellular Disease Modeling, 2019 20th International Conference on Solid-State Sensors, Actuators and Microsystems & Eurosensors XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), Berlin, Germany, 2019, pp. 1686-1689, DOI: 10.1109/TRANSDUCERS.2019.8808364.
Makerspace microfabrication of a stainless steel 3D microneedle electrode array (3D MEA) on a glass substrate for simultaneous optical and electrical probing of electrogenic cells, RSC Adv., 2020,10, 41577-41587, https://doi.org/10.1039/D0RA06070D.
Development of in vitro 2D and 3D microelectrode arrays and their role in advancing biomedical research, Journal of Micromechanics and Microengineering, Volume 30, Number 10.
Researchers at the University of Central Florida and Axosim Technologies, Inc. have developed a 3D microelectrode array for use in microengineered physiological systems that can detect multiple bioelectrical signals reliably in real time and up to a year. By enabling higher throughput, the invention supports the large-scale screening of therapeutic compounds.
Though traditional microengineered physiological systems provide in vivo information in an in vitro setting, the electrophysiological testing requires labor-intensive manual placement of stimulating and recording electrodes using micromanipulators. The process hampers the rate of testing compared to other higher throughput 2D multi-electrode array (MEA) systems. Additionally, conventional planar MEAs cannot capture signals that occur at a certain height when cultures mature to obtain a 3D form.
As a solution, microengineered physiological systems can be integrated with the UCF 3D microelectrode array to automate the process of stimulation, recording or both. Compared to 2D MEA platforms, the 3D electrodes enable a system to interrogate many diverse axonal fibers to realize population-based electrophysiological responses that are more akin to in vivo nerve tissue. It can also capture and analyze signals from thicker, mature tissues, which is especially important in neurological models on a chip. The microelectrode arrays can be used to study pathophysiological mechanisms of toxicity, disease, or any agent within any cell population or to study such effects on any aspect or component of a cell.
Technical Details
The invention is a 3D microelectrode array and methods for fabricating it for use in a microengineered physiological system. It comprises a chip of biocompatible material that can maintain the viability of neuronal cells and can interface with standard commercial multichannel systems and standard commercial recording amplifiers. The chip can consist of at least one 2D electrode, one 3D electrode, or a combination. Complementary to the neural architecture, the array can include various regions, such as an axonal growth region, a ganglion region, a dendritic region, a synaptic region, and a spheroid region. The bioelectrical signals can be single action potentials, compound action potentials, high-frequency waves, low-frequency waves, or various combinations.
In one example application, a microelectrode design can be integrated into a 3D hydrogel environment, enabling rapid electrophysiological testing to study any contents of a cell. This includes organelles, subcellular organelles, cell cytoplasm, or structures within the cell membrane. Certain embodiments can be applied to study microtubules, chromosomes, DNA, RNA, mitochondria, ribosomes, Golgi apparatus, lysosomes, endoplasmic reticulum, vacuoles, or fragments of such items.
Partnering Opportunity
The research team is seeking partners for licensing and/or research collaboration.
Researchers at the University of Central Florida have developed methods for microfabricating and assembling three-dimensional microelectrode arrays (3D MEAs) based on a glass-stainless steel platform. The technology uses non-traditional “makerspace microfabrication” techniques that enable the cost-effective fabrication of a device using biocompatible materials.
3D MEAs provide signal acquisition for 3D cell cultures, making them superior to 2D arrays, which provide planar cell cultures. However, 3D MEAs are more expensive and harder to fabricate. The UCF fabrication technology, however, is simple in its design and uses inexpensive components (stainless steel, glass, conductive resins) and materials. It also combines electrical and optical probing capabilities and can be scaled appropriately for more extensive and customizable array configurations.
Technical Details
The cost-effective UCF technology comprises non-traditional “makerspace microfabrication” techniques using various biocompatible materials to produce 3D MEAs rapidly and efficiently. The 3D MEAs may include a substrate body (for example, a chip), microneedles, traces, and a well for transferring electrical signals from one side of the substrate body to the other side of the body. Included are methods for using 3D MEAs to grow electrogenic cells and obtain electrophysiological signals. Additionally, the researchers developed a unique interconnect interface using 3D printing and conductive ink casting. The interconnect transitions the electrical contact from the topside of the glass chip to the bottom side of the device, exhibiting high electrical conductivity and demonstrating its effectiveness as an interconnect for a biological microdevice.
In one example application, stainless steel electrodes are planar laser micromachined and transitioned out-of-plane to have a 3D configuration of 400 µm high and 300 µm wide. The 2D to 3D transition angles are consistently perpendicular to the micromachining plane. Methods include bonding the laser micromachined 3D stainless steel onto a glass die and routing metal traces to the edge of the chip. With the glass substrate, the device can optically and electrically probe electrogenic cells to measure their electrophysiological activities. Confined precision drop-casting (CPDC) of polydimethylsiloxane (PDMS) defines uniform insulation for the 3D MEA.
Partnering Opportutnity
The research team is looking for partners to develop the technology further for commercialization.
Stage of Development
Prototype available.
Makerspace microfabrication of a stainless steel 3D microneedle electrode array (3D MEA) on a glass substrate for simultaneous optical and electrical probing of electrogenic cells, RSC Adv., 2020,10, 41577-41587, https://doi.org/10.1039/D0RA06070D.
The University of Central Florida invention is a novel two-step, makerspace-based microfabrication strategy for creating high-throughput (HT), self-insulated 3D microelectrode arrays (MEAs). Microstereolithography (µSLA)-based 3D printing technology not only allows for the realization of 3D microelectrode geometries but also enables the monolithic integration of all components of the “bio plate” (standard culture wells) to realize the HT, American National Standards Institute (ANSI)/Society for Lab Automation and Screening (SLAS)-compatible geometry in 1 to 768 well (or more wells) configurations. This approach enables a rapid, accurate, cost-effective, two-step scaling up technique to microfabricate HT-3D microelectrode arrays in several multiwell designs compatible with standard HT assay equipment such as plate readers, robotic handlers, and electrophysiological systems.
Development of a 3D Printed, Self-Insulated, High-Throughput 3D Microelectrode Array (HT-3DMEA), Journal of Microelectromechanical Systems, vol. 29, no. 5, pp. 1091-1093, Oct. 2020, doi: 10.1109/JMEMS.2020.3003644.
The University of Central Florida invention is a polymer and metal-based microfabrication technology for 3D microelectrode arrays (3D MEAs). The device incorporates “tri-modal functionality” for obtaining simultaneous data sets comprising electrical, optical and microfluidic markers from a variety of electrogenic cellular constructs. 3D MEAs are the next-generation interfaces for “organ-on-a-chip” in vitro modeling of biological functions. Rapid neuronal spheroid attachment to the 3D microfluidic ports of the tri-modal 3D MEA has been demonstrated successfully.
The University of Central Florida invention is a polymer and metal-based microfabrication technology toward biosensors. The technology provides penta-modal functionalities for obtaining simultaneous data sets comprising electrical, optical and microfluidic markers from a variety of electrogenic cellular constructs. 3D MEAs are considered the prime electrical modality for obtaining relevant 1kHz electrophysiology in the expanding "organ-on-a-chip" field. In vitro modeling of biological functions is becoming ever more important as the scientific community looks for novel methods in drug development and personalized medicine. The UCF microfabrication process is a highly specific micro-milling, drilling and rastering combination to realize a complex device geometry in relatively little time.
Partnering Opportunity
The research team is seeking partners for licensing and/or research collaboration.
Stage of Development
Prototype available.
The University of Central Florida invention is a 3D-printed, multilevel, fully packaged, microfluidic platform with an innovative metallization approach using liquid metal. Cost-effective, scalable and customizable, the innovation offers enhanced multi-modality for multi-phase control in the microchamber microenvironment. The UCF technology provides a monolithically 3D-printed array of microchannels in a multilayer circuit with an integrated microchamber. Microchannels at different levels are conduits towards a centrally located 2.5D microelectrode array (MEA) to stimulate/record electrogenic spheroids electrically. The microchannels also serve as inlets/outlets for injecting/suctioning liquids (for example, samples, reagents). The microchamber allows for controlling/isolating the cultured microenvironment and perfusing gases (such as O2, CO2) for electroactive responses. The device was characterized with synthetic organoids under phosphate buffer saline (PBS) and sample gas (oxygen) injection. Impedance responses to the changing microenvironment were studied, as was multi-metallic sheet resistance. Barrier integrity and coverage of the synthetic organoid matrix are also determined from frequency analysis.
Partnering Opportunity
The research team is seeking partners for licensing, research collaboration, or both.
Stage of Development
Prototype available.