Methods and apparatus for separating live from dead organisms in a sample
Inventors
Weber, Monika • Antoszczyk, Slawomir • Weber, Robert
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11891594-B2
Publication Date
2024-02-06
Expiration Date
Abstract
Methods and apparatus for detecting, quantifying, enriching, and/or separating bacterial species in fluid sample are provided. The fluid sample is provided as input to a microfluidic passage of a microfluidic device, wherein the microfluidic device comprises at least one electrode disposed adjacent to the microfluidic passage. The at least one electrode is activated to capture bacteria in the sample using dielectrophoresis, wherein the capture efficiency of bacteria is at least 99%.
Core Innovation
The invention provides a method in which a fluid sample is supplied to a microfluidic passage of a microfluidic device, the passage having at least one electrode system disposed adjacent to the passage. The electrode system is driven by an AC voltage generated by at least one signal generator, and includes a first electrode system and a second electrode system. Generating a first AC voltage and a second AC voltage causes selective capture by positive dielectrophoresis on different electrode surfaces.
The first AC voltage has first characteristics that cause the first electrode system to selectively capture only the live organisms on the surface of at least one first electrode by positive dielectrophoresis. The second AC voltage has second characteristics that cause the second electrode system to selectively capture only the dead organisms on the surface of at least one second electrode by positive dielectrophoresis.
After these selective captures, the method images the at least one first electrode while the live organisms are captured to generate one or more first images. The method then processes, using a computer, the one or more first images to detect and/or quantify the live organisms, and can also image and process the at least one second electrode to detect and/or quantify the dead organisms.
In further refinements reflected by the dependent claim set, the method can include generating additional AC voltages after capture to release captured organisms by negative dielectrophoresis, and the first and second electrode systems can include arrays of electrodes positioned along different portions of a microfluidic passage in at least one dimension.
Claims Coverage
The provided material identifies one independent claim covering a microfluidic, electrode-driven AC dielectrophoresis workflow combined with optical imaging and computer processing to detect and/or quantify organisms. The dependent claims add imaging and processing of dead-capture electrodes, release by negative dielectrophoresis, electrode-array structure, and an AC voltage frequency constraint.
Microfluidic passage with adjacent electrode systems for AC driving
A fluid sample is supplied to a microfluidic passage of a microfluidic device, the passage having at least one electrode system disposed adjacent to the microfluidic passage, and at least one AC voltage drives the electrode system.
Selective positive dielectrophoresis capture of live and dead organisms on different electrode systems
A first AC voltage causes the first electrode system to selectively capture only live organisms on at least one first electrode by positive dielectrophoresis, and a second AC voltage causes the second electrode system to selectively capture only dead organisms on at least one second electrode by positive dielectrophoresis.
Optical imaging of live capture and computer processing for detection and quantification
The at least one first electrode is imaged while live organisms are captured to generate one or more first images, and a computer processes the images to detect and/or quantify the live organisms.
Imaging and processing of dead capture on the second electrode system
The at least one second electrode is imaged while dead organisms are captured to generate second images, and a computer processes the images to detect and/or quantify the dead organisms.
Release of captured organisms using negative dielectrophoresis with additional AC voltages
After capture, additional AC voltages drive the first or second electrode system to release captured organisms from the electrode surface by negative dielectrophoresis.
Electrode-array structure along different portions of the microfluidic passage
The first and second electrode systems include arrays of electrodes positioned along different portions of a microfluidic passage in at least one dimension.
AC voltage frequency constraint for selective capture characteristics
The frequency of the first AC voltage is at least 25 MHz.
The claims focus on driving adjacent electrode systems in a microfluidic passage with AC voltages that selectively capture live organisms on a first electrode system and dead organisms on a second electrode system by positive dielectrophoresis, followed by optical imaging and computer processing to detect and/or quantify. Dependent refinements further add imaging and quantification for dead organisms, release of captured organisms using negative dielectrophoresis, and structural and frequency constraints.
Stated Advantages
Selectively capture only live organisms on a first electrode system surface by positive dielectrophoresis.
Selectively capture only dead organisms on a second electrode system surface by positive dielectrophoresis.
Detect and/or quantify the live organisms in one or more first images using computer processing.
Optionally detect and/or quantify dead organisms by imaging and computer processing of images of the second electrode.
Optionally release captured organisms from electrode surfaces using negative dielectrophoresis by generating additional AC voltages.
Documented Applications
Not explicitly described in patent.
Interested in licensing this patent?