Stimuli-responsive polymer diagnostic assay comprising magnetic nanoparticles and capture conjugates

Patent metadata

Field	Value
Publication number	US-9429570-B2
Application number	US-201514732428-A
Country	US
Kind code	B2
Filing date	Jun 5, 2015
Priority date	Nov 9, 2009
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

The present disclosure utilizes the aggregation of stimuli-responsive polymers to isolate a diagnostic target (e.g., an antigen) from a solution using magnetophoresis. Isolating the diagnostic target provides a route to identify the presence of the diagnostic target in the solution.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of concentrating a target in a liquid, comprising applying a magnetic field to an aggregate in the liquid to provide a collected aggregate by magnetophoresis, wherein the aggregate comprises:
(a) a stimuli-responsive magnetic nanoparticle comprising a first stimuli-responsive polymer attached to a magnetic core; and
(b) a stimuli-responsive capture conjugate comprising a second stimuli-responsive polymer attached to a capture moiety, wherein the capture moiety is capable of binding to a target;
wherein the aggregate is formed through associative interaction between the first stimuli-responsive polymer and the second stimuli-responsive polymer.

2. The method of claim 1 , wherein the magnetic field does not induce magnetophoresis in a non-aggregated stimuli-responsive magnetic nanoparticle in the liquid.

3. The method of claim 1 further comprising a step of concentrating the aggregate in the liquid.

4. The method of claim 1 , wherein the first stimuli-responsive polymer and the second stimuli-responsive polymer are responsive to stimuli independently selected from the group consisting of temperature, pH, light, photo-irradiation, exposure to an electric field, ionic strength, and combinations thereof.

5. The method of claim 1 , wherein the stimuli-responsive capture conjugate further comprises a detector complex comprising a detector moiety and a second capture moiety, wherein the second capture moiety is capable of binding to the target.

6. The method of claim 1 , wherein the target is an indicator for a disease or condition.

7. The method of claim 1 , wherein the target is selected from the group consisting of an antibody, an antigen, a cell, a nucleic acid, an enzyme, a substrate for an enzyme, a protein, a lipid, a carbohydrate, or other biomarker.

8. The method of claim 1 further comprising a biological sample selected from the group consisting of blood, mucus, urine, tissue, sputum, saliva, feces, a nasal swab, and nasopharyngeal washes.

9. The method of claim 1 , wherein the magnetic core is a metal oxide.

10. The method of claim 1 further comprising a second stimuli-responsive capture conjugate comprising a third stimuli-responsive polymer attached to a third capture moiety, wherein the third capture moiety is capable of capturing a second target, wherein the second target is different than the target.

11. A stimuli-responsive reagent, comprising:
(a) a stimuli-responsive magnetic nanoparticle comprising a first stimuli-responsive polymer attached to a magnetic core; and
(b) a stimuli-responsive capture conjugate comprising a second stimuli-responsive polymer attached to a first capture moiety, wherein the first capture moiety is capable of binding to a target.

12. The stimuli-responsive reagent of claim 11 , wherein the first stimuli-responsive polymer and the second stimuli-responsive polymer are responsive to stimuli independently selected from the group consisting of temperature, pH, light, photo-irradiation, exposure to an electric field, ionic strength, and combinations thereof.

13. The stimuli-responsive reagent of claim 11 , wherein the stimuli-responsive reagent further comprises a detector complex comprising a detector moiety and a second capture moiety, wherein the second capture moiety is capable of binding to the target.

14. The stimuli-responsive reagent of claim 11 , wherein the target is an indicator for a disease or condition.

15. The stimuli-responsive reagent of claim 11 , wherein the target is selected from the group consisting of an antibody, an antigen, a cell, a nucleic acid, an enzyme, a substrate for an enzyme, a protein, a lipid, a carbohydrate, or other biomarker.

16. The stimuli-responsive reagent of claim 11 , wherein the magnetic core is a metal oxide.

17. The stimuli-responsive reagent of claim 11 further comprising a second stimuli-responsive capture conjugate comprising a third stimuli-responsive polymer attached to a third capture moiety, wherein the third capture moiety is capable of capturing a second target, wherein the second target is different than the target.

18. A method of capturing a target in a liquid, comprising:
(a) contacting a liquid to be tested for the presence of a target with a stimuli-responsive reagent for a pre-determined period of time sufficient to effect binding of the target, if present, to the stimuli-responsive capture conjugate, comprising:
(i) a stimuli-responsive magnetic nanoparticle comprising a first stimuli-responsive polymer attached to a magnetic core; and
(ii) a stimuli-responsive capture conjugate comprising a second stimuli-responsive polymer attached to a capture moiety, wherein the capture moiety is capable of binding to a target;

(b) applying an effective stimulus to provide an aggregate in the liquid formed through associative interaction between the first stimuli-responsive polymer and the second stimuli-responsive polymer, wherein the aggregate comprises:
(i) a stimuli-responsive magnetic nanoparticle comprising a first stimuli-responsive polymer attached to a magnetic core; and
(ii) a stimuli-responsive capture conjugate comprising a second stimuli-responsive polymer attached to a capture moiety, wherein the capture moiety is bound to the target when the target is present in the liquid,

(c) subjecting the aggregate to a magnetic field to magnetophorese the aggregate to a site within the liquid to provide a magnetophoresed aggregate in the liquid; and
(d) analyzing the magnetophoresed aggregate to determine if the target is present.

19. The method of claim 18 further comprising binding a detector complex to the target, said detector complex comprising a second capture moiety capable of binding to the target and a reporting moiety.

20. The method of claim 19 , wherein the step of analyzing the magnetophoresed aggregate comprises photoluminescence analysis.

Assignees

• Univ Washington Through Its Center For Commercialization

Inventors

• Stayton Patrick S
• Lai Jriuan
• Nehilla Barrett J
• Srinivasan Selvi

Classifications

• G01N2001/4088

  filtration · CPC title

• B03C2201/18

  Magnetic separation whereby the particles are suspended in a liquid · CPC title

• C12N15/1013

  by using magnetic beads · CPC title

• G01N33/545

  Synthetic resin · CPC title

• G01N2001/4038

  electric methods, e.g. electromigration, electrophoresis, ionisation · CPC title