Stimuli-responsive polymer diagnostic assay comprising magnetic nanoparticles and capture conjugates
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.
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, wherein the stimuli-responsive magnetic nanoparticle does not include a capture moiety; 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, wherein the stimuli-responsive magnetic nanoparticle does not include a capture moiety; 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 reagent, wherein the stimuli-responsive reagent comprises:
(i) a stimuli-responsive magnetic nanoparticle comprising a first stimuli-responsive polymer attached to a magnetic core, wherein the stimuli-responsive magnetic nanoparticle does not include a capture moiety; 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 the stimuli-responsive magnetic nanoparticle and the stimuli-responsive capture conjugate, and 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.
21. The method of claim 1 , wherein the stimuli-responsive capture conjugate does not include a magnetic nanoparticle.
22. The method of claim 1 , wherein the stimuli-responsive magnetic nanoparticle consists of the first stimuli-responsive polymer attached to the magnetic core.
23. The stimuli-responsive reagent of claim 11 , wherein the stimuli-responsive capture conjugate does not include a magnetic nanoparticle.
24. The stimuli-responsive reagent of claim 11 , wherein the stimuli-responsive magnetic nanoparticle consists of the first stimuli-responsive polymer attached to the magnetic core.
25. The method of claim 18 , wherein the stimuli-responsive capture conjugate does not include a magnetic nanoparticle.
26. The method of claim 18 , wherein the stimuli-responsive magnetic nanoparticle consists of the first stimuli-responsive polymer attached to the magnetic core.