Determining a bulk concentration of a target in a sample using a digital assay with compartments having nonuniform volumes

Patent metadata

Field	Value
Publication number	US-11305284-B2
Application number	US-201816200447-A
Country	US
Kind code	B2
Filing date	Nov 26, 2018
Priority date	Nov 26, 2018
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

An embodiment of a system includes a compartment-generating device, a compartment detector, and electronic computing circuitry. The device is configured to generate compartments of a digital assay, at least one of the compartments having a respective volume that is different from a respective volume of each of at least another one of the compartments. The detector is configured to determine a number of the compartments each having a respective number of a target that is greater than a threshold number of the target. And the electronic circuitry is configured to determine a bulk concentration of the target in a source of the sample in response to the determined number of compartments. Because such a system can be configured to estimate a bulk concentration of a target in a source from a polydisperse digital assay, the system can be portable, and lower-cost and faster, than conventional systems.

First claim

The invention claimed is:

1. A system, comprising:
a device configured to generate compartments of a sample, at least one of the compartments having a respective volume that is different from a respective volume of each of at least another one of the compartments;
a detector configured to determine a characterized number of the compartments each having a respective number of a target that is greater than a threshold number of the target and a characterized volume for each of the compartments having the target greater than the threshold number; and
a microprocessor including firmware to determine a bulk concentration of the target in a source of the sample by generating an estimate of the bulk concentration in response to the characterized number of the compartments having the target greater than the threshold number and the characterized volume for each of the compartments having the target greater than the threshold number, wherein the bulk concentration is determined by a digital-variable-volume-approximation (DVVA) algorithm.

2. The system of claim 1 wherein the device includes a container configured to generate the compartments of the sample as droplets of the sample in an oil in response to a shaking of the container.

3. The system of claim 1 wherein the device includes a container configured to generate the compartments of the sample as droplets of the sample in a barrier phase in response to a shaking of the container, the droplets each have a viscosity, the barrier phase having a viscosity that is greater than the viscosity of the droplets.

4. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a respective measured volume of each of the number of compartments.

5. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a sum of a respective measured volume of each of the compartments.

6. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a number of the compartments.

7. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a number of other compartments.

8. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a respective measured volume of each of other compartments.

9. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a number of other compartments and a respective measured volume of each of the other compartments.

10. The system of claim 1 wherein the microprocessor including firmware is configured to determine a bulk concentration of the target in a source of the sample in response to a probability density function of compartment volume.

11. A system, comprising:
a barrier-phase liquid;
a container configured to receive the barrier-phase liquid, to receive a sample including a target, and to generate compartments of the sample suspended in the barrier-phase liquid in response to a shaking of the container, at least one of the compartments having a respective volume that is different from a respective volume of each of at least another one of the compartments;
a detector configured to determine a characterized number of the compartments each having a respective number of the target that is greater than a threshold number of the target and a characterized volume for each of the compartments having the target greater than the threshold number; and
a microprocessor including firmware to determine a bulk concentration of the target in a source of the sample by generating an estimate of the bulk concentration in response to the characterized number of the compartments having the target greater than the threshold number and the characterized volume for each of the compartments having the target greater than the threshold number, wherein the bulk concentration is determined by a digital-variable-volume-approximation (DVVA) algorithm.

12. The system of claim 11 wherein the barrier-phase liquid includes an oil.

13. The system of claim 11 wherein the container includes a clear tube.

14. The system of claim 11 wherein the detector includes an electronic detector.

15. The system of claim 11 wherein the detector is configured to determine a number of the compartments.

16. The system of claim 11 , further comprising an apparatus configured to obtain the sample from a source including the target.

Assignees

• Tokitae Llc

Inventors

• Huynh Toan
• Weigl Bernhard Hans
• Byrnes Samantha A
• Nichols Kevin Paul Flood

Classifications

• B01L3/5082 Primary

  Test tubes per se · CPC title

• C12Q1/6844

  Nucleic acid amplification reactions · CPC title

• C12Q1/6816

  characterised by the detection means (C12Q1/6804 takes precedence) · CPC title

• G01N33/18

  Water · CPC title

• B01L2300/0832

  cylindrical, tube shaped · CPC title