Microfluidics-based nanobiosensors and devices

Patent metadata

Field	Value
Publication number	US-11318470-B2
Application number	US-201716349700-A
Country	US
Kind code	B2
Filing date	Nov 17, 2017
Priority date	Nov 18, 2016
Publication date	May 3, 2022
Grant date	May 3, 2022

Abstract

Microfluidic devices and nanobiosensors comprising a magnetic nanoparticle attached to a reporter molecule via a release unit for microfluidic-based detection of a target analyte in a biological sample. The nanobiosensors can be magnetically manipulated or guided through the microfluidics channels for incubation with the biological sample, concentration of the nanobiosensors, and detection of target analytes, without having to pump the entire initial sample through a microfluidic channel of the microfluidic device. The magnetic nanoparticles are separated from the reporter molecules before detection and can be re-used.

First claim

The invention claimed is:

1. A method of microfluidic detection of a target analyte in a biological sample collected from a subject, the method comprising:
providing a microfluidic device, said device comprising:
a planar substrate comprising a sample inlet well positioned above a sample chamber in or on the substrate and a detection chamber in fluid communication with the sample chamber via a microfluidic channel extending from the sample chamber to the detection chamber; and a washing chamber positioned along the microfluidic channel intermediate to the sample chamber and the detection chamber; and
a magnet positioned external and adjacent to said microfluidic channel, wherein said magnet is translatable along a plane parallel and to the plane of said microfluidic channel;

incubating said biological sample with a first nanobiosensor in said sample chamber, wherein said first nanobiosensor comprises a magnetic nanoparticle releasably attached to a plurality of reporter molecules;
transferring said incubated sample and said first nanobiosensor to said wash chamber;
introducing a wash fluid into said wash chamber to yield a first washed nanobiosensor;
magnetically transferring said first washed nanobiosensor to said detection chamber by translating said magnet along a plane parallel to said microfluidic channel from a position adjacent said wash chamber to a position adjacent said detection chamber;
separating said nanoparticle and said reporter molecules to yield separated reporter molecules and a delinked nanoparticle,
magnetically removing said delinked nanoparticle from said detection chamber by translating said magnet along a plane parallel to said microfluidic channel away from said detection chamber;
detecting said separated reporter molecules in said detection chamber by microfluidic Isoelectric Focusing of said separated reporter molecules and detecting locations of said separated reporter molecules in said detection chamber, wherein said reporter molecules are indicative of interaction of said target analyte with said reporter molecules.

2. The method of claim 1 , wherein said magnetic nanoparticle is releasably attached to a plurality of said reporter molecules via respective release units, wherein said release units are selected from the group consisting of reducible disulfide bridge, pH-sensitive linkage, photosensitive linkage, and thermosensitive linkages.

3. The method of claim 1 , wherein said magnetic nanoparticle comprises any type of ferromagnetic metal (including elemental metal) or metal alloy selected from the group consisting of iron (Fe), nickel (Ni), cobalt (Co), certain alloys of rare-earth metals, and the oxides, hydroxides, sulfides, selenides, and tellurides of the foregoing, and combinations thereof.

4. The method of claim 1 , wherein said magnetic nanoparticle is a core/shell nanoparticle selected from the group consisting of Fe/Au, Fe(0)/Fe 3 O 4 , and Au/Fe 2 O 3 .

5. The method of claim 1 , wherein said reporter molecules are peptide sequences comprising a target analyte recognition sequence, detectable label, and one or more optional pI tag(s).

6. The method of claim 5 , wherein said recognition sequence is selected from the group consisting of a supramolecular recognition sequence, a protease consensus sequence, and a post-translationally modifiable sequence.

7. The method of claim 5 , wherein said detecting comprises exposing said detection chamber to an energy source to generate a detectable signal from said detectable label.

8. The method of claim 1 , wherein said incubating comprises mixing said biological sample and said nanobiosensor by rotating said magnet in a position adjacent to said sample chamber, thereby magnetically moving said nanobiosensors throughout said biological sample.

9. The method of claim 1 , wherein said magnet is positioned on a translatable stage below said microfluidic channel.

10. The method of claim 1 , wherein said microfluidic channel further comprises one or more valves to provide forward and/or back pressure in said channel.

11. The method of claim 1 , further comprising removing a portion of said biological sample via a waste outlet prior to magnetically transferring said first washed nanobiosensor to said detection chamber.

12. The method of claim 11 , wherein said first nanobiosensor is present in said biological sample in a first concentration in said sample chamber; and wherein said washed nanobiosensor is present in a second concentration in said detection chamber, wherein said second concentration is greater than said first concentration.

13. The method of claim 1 , wherein said detection chamber further comprises one or more inlets for applying an electrical current into said detection chamber.

14. The method of claim 1 , further comprising incubating a plurality of additional nanobiosensors with said biological sample and first nanobiosensor in said sample chamber, wherein said plurality of additional nanobiosensors each comprise respective reporter molecules, wherein said respective reporter molecules are specific for a different target analyte than said first nanobiosensor.

15. The method of claim 14 , wherein said separated reporter molecules are configured in a linearly spaced array of reporter molecules at respective locations in said detection chamber.

16. The method of claim 15 , further comprising exposing said array to a light source and optically detecting the configuration of said array.

17. The method of claim 16 , further comprising detecting the intensity of a detectable signal from said separated reporter molecules.

Assignees

• Univ Kansas State

Inventors

• Culbertson Christopher T
• Bossmann Stefan H

Classifications

• B01L2400/043

  magnetic forces · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• B01L3/502761 Primary

  specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads or physically stretching molecules · CPC title

• G01N1/38

  Diluting, dispersing or mixing samples · CPC title

• C07K1/24

  by electrochemical means · CPC title