Biological detector and method
View Patent ↗A biological detector includes a conduit for receiving a fluid containing one or more magnetic nanoparticle-labeled, biological objects to be detected and one or more permanent magnets or electromagnet for establishing a low magnetic field in which the conduit is disposed. A microcoil is disposed proximate the conduit for energization at a frequency that permits detection by NMR spectroscopy of whether the one or more magnetically-labeled biological objects is/are present in the fluid.
1. A detector, comprising:
a magnetic field generator for providing a magnetic field lower than that of a superconducting magnet associated with nuclear magnetic resonance (NMR) detection;
a conduit for a fluid comprising at least one magnetically-labeled biological object, the conduit disposed within the magnetic field; and
a microcoil proximate the conduit for providing energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled biological object in the fluid.
2. The detector of claim 1 , wherein the magnetic field generator comprises at least one permanent magnet.
3. The detector of claim 1 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled biological object, the magnetic label having a magnetic moment sufficient for detection within said magnetic field when at least singly bound to said biological object.
4. The detector of claim 1 , wherein the magnetic field is about 0.5 T to about 1.5 T.
5. The detector of claim 1 , wherein the conduit comprises a capillary tube.
6. The detector of claim 1 , wherein the microcoil comprises a solenoid-shaped coil disposed about the conduit.
7. The detector of claim 1 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
8. The detector of claim 1 , wherein the microcoil has an inner diameter of about 75 to about 125 microns.
9. The detector of claim 1 , wherein the microcoil has an inner diameter of about 100 microns.
10. The detector of claim 1 , wherein the microcoil comprises metallic wire disposed about the conduit.
11. The detector of claim 1 , wherein the microcoil comprises metallic material deposited about the conduit.
12. The detector of claim 1 , wherein the microcoil comprises a planar coil.
13. The detector of claim 1 , wherein the conduit and the microcoil are disposed on a substrate.
14. The detector of claim 1 , wherein the conduit and the microcoil are disposed on a ceramic substrate.
15. The detector of claim 1 , wherein the conduit and the microcoil are disposed on a chip.
16. The detector of claim 1 , wherein the NMR detection comprises identification of the at least one magnetically-labeled biological object.
17. The detector of claim 1 , wherein the NMR detection comprises determination of a presence or an absence of the at least one magnetically-labeled biological object.
18. The detector of claim 1 , wherein the frequency is 44.2 MHz or less.
19. The detector of claim 1 , wherein the microcoil has an inductance of 93 nH or less.
20. The detector of claim 1 , wherein the microcoil and a tuning circuit form an electrical circuit, the tuning circuit sufficient for tuning the microcoil to resonance at a frequency of 44.2 MHz or less.
21. The detector of claim 20 , wherein the microcoil has an inductance of 93 nH or less.
22. The detector of claim 20 , wherein the tuning circuit is sufficient to provide an input impedance for the electrical circuit.
23. The detector of claim 20 , wherein the tuning circuit is sufficient to transform the impedance of the microcoil.
24. The detector of claim 20 , wherein the tuning circuit comprises capacitors.
25. The detector of claim 20 , wherein the tuning circuit comprises an inductor in series or in parallel with the microcoil.
26. A detector, comprising:
a magnetic field generator for providing a magnetic field lower than that of a superconducting magnet associated with nuclear magnetic resonance (NMR) detection;
a conduit for a fluid comprising at least one magnetically-labeled biological object, the conduit disposed within the magnetic field;
a microcoil proximate the conduit for providing energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled biological object in the fluid; and
a tuning circuit for forming an electrical circuit with the microcoil, the tuning circuit sufficient for tuning the microcoil to a resonance frequency of said fluid.
27. The detector of claim 26 , wherein the magnetic field generator comprises at least one permanent magnet.
28. The detector of claim 26 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled biological object, the magnetic label having a magnetic moment sufficient for detection within said magnetic field when at least singly bound to said biological object.
29. The detector of claim 26 , wherein the magnetic field is about 0.5 T to about 1.5 T.
30. The detector of claim 26 , wherein the microcoil comprises a solenoid-shaped coil disposed about the conduit.
31. The detector of claim 26 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
32. The detector of claim 26 , wherein the frequency is 44.2 MHz or less.
33. The detector of claim 26 , wherein the microcoil has an inductance of 93 nH or less.
34. The detector of claim 26 , wherein the tuning circuit is sufficient to provide an input impedance for the electrical circuit.
35. The detector of claim 26 , wherein the tuning circuit is sufficient to transform the impedance of the microcoil.
36. The detector of claim 26 , wherein the tuning circuit comprises capacitors.
37. The detector of claim 26 , wherein the tuning circuit comprises an inductor in series or in parallel with the microcoil.
38. A method of detection, comprising:
providing a magnetic field lower than that of a superconducting magnet associated with nuclear magnetic resonance (NMR) detection;
disposing a fluid comprising at least one magnetically-labeled biological object within the magnetic field and proximate a microcoil; and
activating the microcoil to provide energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled biological object in the fluid.
39. The method of claim 38 , wherein said providing comprises providing the magnetic field via at least one permanent magnet.
40. The method of claim 38 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled biological object, the magnetic label having a magnetic moment sufficient for detection within said magnetic field when at least singly bound to said biological object.
41. The method of claim 38 , wherein the magnetic field is about 0.5 T to about 1.5 T.
42. The method of claim 38 , wherein the fluid comprises an aqueous fluid.
43. The method of claim 38 , wherein the fluid comprises at least one magnetic label associated with the at least one magnetically-labeled biological object, the at least one magnetic label comprises a paramagnetic nanoparticle.
44. The method of claim 38 , wherein said disposing comprises disposing the fluid in a conduit.
45. The method of claim 44 , wherein the microcoil comprises a solenoid-shaped coil disposed about the conduit.
46. The method of claim 38 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
47. The method of claim 38 , wherein the microcoil has an inner diameter of about 75 to about 125 microns.
48. The method of claim 38 , wherein the microcoil has an inner diameter of about 100 microns.
49. The method of claim 38 , wherein the NMR detection comprises identification of the at least one magnetically-labeled biological object.
50. The method of claim 38 , wherein the NMR detection comprises determination of a presence or an absence of the at least one magnetically-labeled biological object.
51. The method of claim 38 , wherein the frequency is 44.2 MHz or less.
52. The method of claim 38 , wherein the microcoil has an inductance of 93 nH or less.
53. The method of claim 38 , further comprising tuning the microcoil to resonance at a frequency of 44.2 MHz or less.
54. The method of claim 53 , wherein the microcoil has an inductance of 93 nH or less.
55. The method of claim 53 , wherein the tuning comprises providing an input impedance for the electrical circuit.
56. The method of claim 53 , wherein the tuning comprises transforming the impedance of the microcoil.
57. The method of claim 53 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises capacitors.
58. The method of claim 53 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises an inductor.
59. A method of detection, comprising:
providing a magnetic field lower than that of a superconducting magnet associated with nuclear magnetic resonance (NMR) detection;
disposing a fluid comprising at least one magnetically-labeled biological object within the magnetic field and proximate a microcoil;
activating the microcoil to provide energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled biological object in the fluid; and
tuning the microcoil to a resonance frequency of the fluid.
60. The method of claim 59 , wherein the magnetic field generator comprises at least one permanent magnet.
61. The method of claim 59 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled biological object, the magnetic label having a magnetic moment sufficient for detection within said magnetic field when at least singly bound to said biological object.
62. The method of claim 59 , wherein the magnetic field is about 0.5 T to about 1.5 T.
63. The method of claim 59 , wherein the microcoil comprises a solenoid-shaped coil disposed about a conduit.
64. The method of claim 59 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
65. The method of claim 59 , wherein the frequency is 44.2 MHz or less.
66. The method of claim 59 , wherein the microcoil has an inductance of 93 nH or less.
67. The method of claim 59 , wherein the tuning comprises providing an input impedance for the electrical circuit.
68. The method of claim 59 , wherein the tuning comprising transforming the impedance of the microcoil.
69. The method of claim 59 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises capacitors.
70. The method of claim 59 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises an inductor.