Raman-active lateral flow device and methods of detection and making
View Patent ↗A lateral flow device is disclosed. The lateral flow device includes a substrate having a flow path and a detection zone disposed along the flow path. The detection zone includes an immobilized target-binding moiety directed against a target of a Raman-active complex. A portion of the detection zone has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone or a first region of the detection zone has a chemical difference from a second region of the detection zone. Also disclosed are methods of conducting a lateral flow assay and methods of making a lateral flow device.
1. A lateral flow device comprising:
a substrate having a flow path; and
a detection zone disposed along the flow path, wherein the detection zone comprises an immobilized target-binding moiety directed against a target of a Raman-active complex; and
wherein a first region of the detection zone has a chemical difference from a second region of the detection zone by having a surface that is at least 20% more hydrophobic than the second region.
2. The lateral flow device of claim 1 , wherein the target comprises at least one target selected from a group consisting of prokaryotic cells, eukaryotic cells, viruses, bacteria, proteins, polypeptides, toxins, liposomes, nucleic acids, and beads.
3. The lateral flow device of claim 1 , wherein the immobilized target-binding moiety comprises at least one moiety selected from a group consisting of antibodies, aptamers, nucleic acids, selective ligands, and polypeptides.
4. The lateral flow device of claim 1 , wherein the detection zone comprises a plurality of immobilized target-binding moieties.
5. The lateral flow device of claim 4 , wherein the plurality of immobilized target-binding moieties are directed against targets different from each other.
6. The lateral flow device of claim 1 , wherein a portion of the detection zone has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone and has a dimension that is less than another dimension of the lateral flow device downflow from the detection zone.
7. The lateral flow device of claim 1 , further comprising a control zone disposed along the flow path downflow from the detection zone, wherein the control zone comprises an immobilized particle-binding-moiety directed against a Raman-active tag.
8. The lateral flow device of claim 7 , wherein the detection zone and control zone are at least partially spatially co-located.
9. The lateral flow device of claim 1 , wherein a portion of the detection zone has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone and wherein the first region of the detection zone has a chemical difference from a second region of the detection zone.
10. The lateral flow device of claim 9 , wherein the dimension of the detection zone is at least 20% less than the another dimension of the lateral flow device upflow from the detection zone.
11. The lateral flow device of claim 10 , wherein the dimension of the detection zone is at least 50% less than the another dimension of the lateral flow device upflow from the detection zone.
12. The lateral flow device of claim 11 , wherein the dimension of the detection zone is at least 75% less than the another dimension of the lateral flow device upflow from the detection zone.
13. The lateral flow device of claim 9 , wherein the dimension of the detection zone comprises width.
14. The lateral flow device of claim 11 , wherein the first region has a surface that is at least 50% more hydrophobic than the second region.
15. The lateral flow device of claim 14 , wherein the first region has a surface that is at least 75% more hydrophobic than the second region.
16. A detection system comprising:
a lateral flow device comprising:
a substrate having a flow path; and
a detection zone disposed along the flow path, wherein the detection zone comprises an immobilized target-binding moiety directed against a target of a Raman-active complex;
wherein a first region of the detection zone has a chemical difference from a second region of the detection zone by having a surface that is at least 20% more hydrophobic than the second region, and
a Raman spectrometer capable of detecting a Raman-active complex at the detection zone.
17. The detection system of claim 16 , wherein the portion of the detection zone has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone.
18. The detection system of claim 16 , wherein the dimension of the detection zone is at least 20% less than the another dimension of the lateral flow device upflow from the detection zone.
19. A method of conducting a lateral flow assay comprising:
i) defining a flow path having a detection zone,
wherein a first region of the detection zone has a chemical difference from a second region of the detection zone by having a surface that is at least 20% more hydrophobic than the second region;
ii) flowing a sample down the flow path, wherein the sample comprises a Raman-active complex or a Raman-active tag; and
iii) immobilizing a Raman-active complex, if present, at the detection zone.
20. The method of claim 19 , wherein immobilizing the Raman-active complex comprises immobilizing the Raman-active complex at a portion of the detection zone that has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone.
21. The method of claim 20 , wherein the dimension of the detection zone is at least 20% less than the another dimension of the lateral flow device upflow from the detection zone.
22. The method of claim 21 , wherein the dimension of the detection zone is at least 50% less than the another dimension of the lateral flow device upflow from the detection zone.
23. The method of claim 22 , wherein the dimension of the detection zone is at least 75% less than the another dimension of the lateral flow device upflow from the detection zone.
24. The method of claim 20 , wherein the dimension comprises width.
25. The method of claim 19 , wherein immobilizing the Raman-active complex comprises immobilizing the Raman-active complex at the second region of the detection zone that chemical differs from the first region of the detection zone.
26. The method of claim 19 , wherein the first region has a surface that is at least 50% more hydrophobic than the second region.
27. The method of claim 26 , wherein the first region has a surface that is at least 75% more hydrophobic than the second region.
28. The method of claim 19 , further comprising generating a Raman spectrum of the Raman-active complex from the detection zone.
29. The method of claim 28 , further comprising correlating the generated Raman spectrum to a presence of a target.
30. The method of claim 28 , further comprising correlating the generated Raman spectrum to an identification of the target.
31. The method of claim 28 , further comprising correlating the generated Raman spectrum to a quantity of the target.
32. The method of claim 19 , wherein the sample comprises a plurality of Raman-active complexes attached to a plurality of targets different from each other.
33. The method of claim 32 , further comprising generating a plurality of Raman spectrums, wherein the plurality of Raman spectrums correlate to the presence of the plurality of targets different from each other.
34. The method of claim 33 , further comprising correlating the plurality of generated Raman spectrums to an identification of the plurality of targets different from each other.
35. The method of claim 33 , further comprising correlating the plurality of generated Raman spectrums to a quantification of the plurality of targets different from each other.
36. The method of claim 19 , wherein flowing the sample comprising providing the Raman-active tags unattached to a target and Raman-active complex simultaneously.
37. The method of claim 19 , wherein flowing the sample comprising providing the Raman-active tags unattached to a target and Raman-active complex sequentially.
38. The method of claim 19 , wherein the Raman-active complex is provided by a target and Raman-active particle.
39. The method of claim 19 , wherein immobilizing the Raman-active complex at the detection zone comprises providing a detection zone having an immobilized target-binding moiety capable of attaching to the target of the Raman-active complex.
40. The method of claim 19 , further comprising a control zone downflow from the detection zone and immobilizing a Raman-active tag at the control zone.
41. The method of claim 40 , wherein immobilizing the Raman-active tag at the control zone comprises providing a control zone having an immobilized particle-binding moiety capable of attaching to the Raman-active tag.
42. A method of conducting a lateral flow assay comprising:
concentrating a Raman-active complex at a portion of a detection zone of a lateral flow assay, wherein the portion of the detection zone has a surface that is at least 20% more hydrophilic than another portion of the detection zone.
43. The method of claim 42 , wherein the Raman-active complex is concentrated at the portion of the detection zone that has a dimension that is less than another dimension of the lateral flow device upflow from the detection zone.
44. The method of claim 43 , wherein the portion of the detection zone has a dimension that is at least 20% less than the another dimension of the lateral flow device upflow from the detection zone.
45. The method of claim 44 , wherein the dimension of the detection zone is at least 50% less than the another dimension of the lateral flow device upflow from the detection zone.
46. The method of claim 42 , wherein the Raman-active complex is concentrated at the portion of the detection zone by a barrier against another portion of the detection.
47. The method of claim 46 , wherein the barrier comprises a plurality of barriers against another portion of the detection zone.
48. The method of claim 42 , wherein the portion of the detection zone has a surface that is at least 50% more hydrophilic than the another portion of the detection zone.
49. A method of making a lateral flow device comprising:
(i) providing a lateral flow device with a detection zone,
wherein a first region of the detection zone has a chemical difference from a second region of the detection zone by having a surface that is at least 20% more hydrophobic than the second region.
50. The method of claim 49 , comprising providing a portion of the detection zone with a dimension that is less than another dimension of the lateral flow device upflow from the detection zone.
51. The method of claim 50 , comprising providing the portion of the detection zone with a dimension that is less than another dimension of the lateral flow device downflow from the detection zone.
52. The method of claim 49 , wherein said providing the first region of the detection zone the chemical difference from the second region of the detection zone comprises treating with at least one member selected from a group consisting of coating, heating, and UV treatment.
53. The method of claim 50 , wherein said providing a portion of the detection zone with a dimension that is less than another dimension of the lateral flow device comprises removing a portion of the detection zone.