Microfluidic sensor

Patent metadata

Field	Value
Publication number	US-11724260-B2
Application number	US-202016841215-A
Country	US
Kind code	B2
Filing date	Apr 6, 2020
Priority date	Apr 8, 2019
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

Provided herein is technology relating to microfluidics and particularly, but not exclusively, to devices, methods, and systems for detecting and/or quantifying analytes in samples using a microfluidic sensor device comprising an oil phase that segments aqueous samples into droplets and provides oil segments that are highly selective chemical sensors for adjacent aqueous droplets.

First claim

We claim:

1. A microfluidic analyte sensing device comprising:
an oil input line and a sample input line that meet at a T-junction or flow-focusing junction;
a sensing oil flowing through the oil input line, wherein the sensing oil comprises a dissolved signaling molecule; and the signaling molecule is specific for an analyte and produces a detectable optical signal in response to contacting the analyte;
a biological sample provided in the sample input line, wherein the sensing oil contacts the biological sample at the T-junction or flow-focusing junction to provide sensing oil segments and sample droplets that flow through a detection channel;
a light source providing light perpendicular to the detection channel and configured to illuminate sensing oil segments in the detection channel without simultaneously illuminating sample droplets; and
a detection means oriented to monitor a signal produced by the sensing oil segments in the detection channel upon being illuminated by the light source.

2. The microfluidic analyte sensing device of claim 1 wherein the sensing oil further comprises a dissolved recognition molecule that is specific for the analyte.

3. The microfluidic analyte sensing device of claim 1 wherein the sensing oil further comprises a dissolved ion exchanger molecule.

4. The microfluidic analyte sensing device of claim 2 wherein the sensing oil further comprises a dissolved ion exchanger molecule.

5. The microfluidic analyte sensing device of claim 1 wherein the sensing oil comprises an oil that is dioctyl sebacate, mineral oil, hexadecane, 4-3-phenylpropylpyridine, dichloroethane, or a fluorous oil.

6. The microfluidic analyte sensing device of claim 1 wherein the signaling molecule comprises a chromoionophore.

7. The microfluidic analyte sensing device of claim 2 wherein the recognition molecule comprises an ionophore.

8. The microfluidic analyte sensing device of claim 1 wherein the sensing oil further comprises a dissolved ion exchanger molecule.

9. The microfluidic analyte sensing device of claim 1 wherein the biological sample is a biofluid.

10. The microfluidic analyte sensing device of claim 1 wherein the biological sample is blood, serum, plasma, urine, tear, sweat, or saliva.

11. The microfluidic analyte sensing device of claim 1 wherein said microfluidic analyte sensing device produces droplets having a volume of 0.05 to 50 nl.

12. The microfluidic analyte sensing device of claim 1 wherein said microfluidic analyte sensing device produces sensing oil segments having a volume of 0.05 to 50 nl.

13. The microfluidic analyte sensing device of claim 1 wherein said microfluidic analyte sensing device produces sensing oil segments at a frequency of 10 to 1000 Hz.

14. The microfluidic analyte sensing device of claim 1 wherein said microfluidic analyte sensing device produces droplets at a frequency of 10 to 1000 Hz.

15. The microfluidic analyte sensing device of claim 1 wherein said microfluidic analyte sensing device is capable of detecting an analyte having a concentration of 1 to 10 −12 M and/or 0.01 to 500 μg/ml in a sample or droplet.

16. A method for detecting and/or quantifying an analyte, the method comprising:
a) providing a microfluidic analyte sensing device comprising a sensing oil, wherein said sensing oil comprises a dissolved signaling molecule that is specific for an analyte and that produces a detectable optical signal in response to contacting the analyte;
b) forming droplets from a biological sample and forming sensing oil segments from said sensing oil, wherein said sensing oil segments flow through a detection channel;
c) illuminating the sensing oil segments using a light source providing light perpendicular to the detection channel, wherein the light source does not simultaneously illuminate the biological sample or droplets;
d) detecting a signal produced by sensing oil segments upon being illuminated by the light source; and
e) detecting and/or quantifying an analyte in one or more of said droplets using the signal produced by the sensing oil segments.

17. The method of claim 16 further comprising producing said sensing oil by dissolving a signaling molecule in an oil to produce said sensing oil; and/or
dissolving a signaling molecule and a recognition molecule in an oil to produce said sensing oil.

18. The method of claim 17 further comprising dissolving an ion exchanger molecule in said oil to produce said sensing oil.

Assignees

• Univ Michigan Regents

Inventors

• Wang Xuewei
• Meyerhoff Mark E
• Castle Bailey Ryan

Classifications

• B01L3/502784 Primary

  specially adapted for droplet or plug flow, e.g. digital microfluidics · CPC title

• B01L3/502715

  characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces · CPC title

• G01N21/33

  using ultraviolet light (G01N21/39 takes precedence) · CPC title

• G01N21/6428

  Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" (in vivo A61B5/00; immunoassay G01N33/53) · CPC title

• G01N21/76

  Chemiluminescence; Bioluminescence · CPC title