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 in association with a fluid proximate the magnetic field; and
a microcoil proximate the magnetic field for providing energy at a frequency sufficient for NMR detection of at least one magnetically-labeled object in the fluid when the fluid is proximate the magnetic field.
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 object, the magnetic field sufficient to lengthen the relaxation time T 2 * of the background fluid without reducing the T 2 *-relaxivity of the at least one magnetic label.
4. The detector of claim 1 , wherein the magnetic field is about 0.5 T to about 1.04 T.
5. The detector of claim 1 , wherein the microcoil comprises a solenoid-shaped coil.
6. The detector of claim 1 , wherein the microcoil comprises a planar coil.
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 , further comprising a conduit proximate the magnetic field.
11. The detector of claim 10 , wherein the conduit comprises a capillary tube.
12. The detector of claim 10 , wherein the conduit is sufficient for fluid flow therethrough.
13. The detector of claim 10 , wherein the microcoil comprises metallic wire disposed about the conduit.
14. The detector of claim 10 , wherein the microcoil comprises metallic material deposited about the conduit.
15. The detector of claim 10 , wherein the microcoil and the conduit are disposed on a substrate.
16. The detector of claim 10 , wherein the microcoil and the conduit are disposed on a ceramic substrate.
17. The detector of claim 10 , wherein the microcoil and the conduit are disposed on a chip.
18. The detector of claim 1 , wherein the fluid comprises an aqueous fluid.
19. The detector of claim 1 , wherein the fluid is optically unclear.
20. The detector of claim 1 , wherein the object is a chemical object and/or a biological object.
21. The detector of claim 1 , wherein the object is dilute relative to the fluid.
22. The detector of claim 1 , wherein the at least one magnetically-labeled object comprises an object labeled via at least one paramagnetic nanoparticle.
23. The detector of claim 1 , wherein the microcoil is sufficient for providing energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled object in the fluid when the fluid is flowing proximate the magnetic field.
24. The detector of claim 1 , wherein the NMR detection comprises identification of the at least one magnetically-labeled object.
25. The detector of claim 1 , wherein the NMR detection comprises determination of a presence or an absence of the at least one magnetically-labeled object.
26. The detector of claim 1 , wherein the NMR detection comprises relaxation time detection.
27. The detector of claim 1 , wherein the NMR detection comprises spectroscopy.
28. The detector of claim 1 , wherein the NMR detection comprises continuous detection.
29. The detector of claim 1 , wherein the frequency is 44.2 MHz or less.
30. The detector of claim 1 , wherein the microcoil has an inductance of 93 nH or less.
31. The detector of claim 1 , further comprising a tuning circuit for forming an electrical circuit with the microcoil, the tuning circuit sufficient for tuning the microcoil to resonance at the frequency.
32. The detector of claim 31 , wherein the tuning circuit is sufficient to provide an input impedance for the electrical circuit.
33. The detector of claim 31 , wherein the tuning circuit is sufficient to transform the impedance of the microcoil.
34. The detector of claim 31 , wherein the tuning circuit comprises capacitors.
35. The detector of claim 31 , wherein the tuning circuit comprises an inductor in series or in parallel with the microcoil.
36. A detector, comprising:
a magnetic field generator for providing a magnetic field sufficient for nuclear magnetic resonance (NMR) detection in association with a fluid flowing proximate the magnetic field; and
a microcoil proximate the magnetic field for providing energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled object in the fluid when the fluid is flowing proximate the magnetic field.
37. The detector of claim 36 , wherein the magnetic field generator comprises at least one permanent magnet.
38. The detector of claim 36 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled object, the magnetic field sufficient to lengthen the relaxation time T 2 * of the background fluid without reducing the T 2 *-relaxivity of the at least one magnetic label.
39. The detector of claim 36 , wherein the magnetic field is lower than that of a superconducting magnet associated with NMR detection.
40. The detector of claim 36 , wherein the magnetic field is about 0.5 T to about 1.04 T.
41. The detector of claim 36 , wherein the microcoil comprises a solenoid-shaped coil.
42. The detector of claim 36 , wherein the microcoil comprises a planar coil.
43. The detector of claim 36 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
44. The detector of claim 36 , wherein the microcoil has an inner diameter of about 75 to about 125 microns.
45. The detector of claim 36 , wherein the microcoil has an inner diameter of about 100 microns.
46. The detector of claim 36 , further comprising a conduit proximate the magnetic field.
47. The detector of claim 46 , wherein the conduit comprises a capillary tube.
48. The detector of claim 46 , wherein the conduit is sufficient for fluid flow therethrough.
49. The detector of claim 46 , wherein the microcoil comprises metallic wire disposed about the conduit.
50. The detector of claim 46 , wherein the microcoil comprises metallic material deposited about the conduit.
51. The detector of claim 46 , wherein the microcoil and the conduit are disposed on a substrate.
52. The detector of claim 46 , wherein the microcoil and the conduit are disposed on a ceramic substrate.
53. The detector of claim 46 , wherein the microcoil and the conduit are disposed on a chip.
54. The detector of claim 36 , wherein the fluid comprises an aqueous fluid.
55. The detector of claim 36 , wherein the fluid is optically unclear.
56. The detector of claim 36 , wherein the object is a chemical object or a biological object.
57. The detector of claim 36 , wherein the object is dilute relative to the fluid.
58. The detector of claim 36 , wherein the at least one magnetically-labeled object comprises an object labeled via at least one paramagnetic nanoparticle.
59. The detector of claim 36 , wherein the NMR detection comprises identification of the at least one magnetically-labeled object.
60. The detector of claim 36 , wherein the NMR detection comprises determination of a presence or an absence of the at least one magnetically-labeled object.
61. The detector of claim 36 , wherein the NMR detection comprises relaxation time detection.
62. The detector of claim 36 , wherein the NMR detection comprises spectroscopy.
63. The detector of claim 36 , wherein the NMR detection comprises continuous detection.
64. The detector of claim 36 , wherein the frequency is 44.2 MHz or less.
65. The detector of claim 36 , wherein the microcoil has an inductance of 93 nH or less.
66. The detector of claim 36 , further comprising a tuning circuit for forming an electrical circuit with the microcoil, the tuning circuit sufficient for tuning the microcoil to resonance at the frequency.
67. The detector of claim 66 , wherein the tuning circuit is sufficient to provide an input impedance for the electrical circuit.
68. The detector of claim 66 , wherein the tuning circuit is sufficient to transform the impedance of the microcoil.
69. The detector of claim 66 , wherein the tuning circuit comprises capacitors.
70. The detector of claim 66 , wherein the tuning circuit comprises an inductor in series or in parallel with the microcoil.
71. A method of detection, comprising:
providing a magnetic field sufficient for nuclear magnetic resonance (NMR) detection in association with a fluid flowing proximate the magnetic field;
flowing a fluid comprising at least one magnetically-labeled object proximate the magnetic field; and
activating a microcoil proximate the magnetic field to provide energy at a frequency sufficient for NMR detection of the at least one magnetically-labeled object in the fluid.
72. The method of claim 71 , wherein the magnetic field generator comprises at least one permanent magnet.
73. The method of claim 71 , wherein the fluid comprises a background fluid and at least one magnetic label associated with the at least one magnetically-labeled object, the magnetic field sufficient to lengthen the relaxation time T 2 * of the background fluid without reducing the T 2 *-relaxivity of the at least one magnetic label.
74. The method of claim 71 , wherein the magnetic field is lower than that of a superconducting magnet associated with NMR detection.
75. The method of claim 71 , wherein the magnetic field is about 0.5 T to about 1.04 T.
76. The method of claim 71 , wherein the microcoil comprises a solenoid-shaped coil.
77. The method of claim 71 , wherein the microcoil comprises a planar coil.
78. The method of claim 71 , wherein the microcoil has an inner diameter of about 50 to about 550 microns.
79. The method of claim 71 , wherein the microcoil has an inner diameter of about 75 to about 125 microns.
80. The method of claim 71 , wherein the microcoil has an inner diameter of about 100 microns.
81. The method of claim 71 , wherein said flowing comprises flowing the fluid via a conduit.
82. The method of claim 81 , wherein the conduit comprises a capillary tube.
83. The method of claim 81 , wherein the conduit is sufficient for fluid flow therethrough.
84. The method of claim 81 , wherein the microcoil comprises metallic wire disposed about the conduit.
85. The method of claim 81 , wherein the microcoil comprises metallic material deposited about the conduit.
86. The method of claim 81 , wherein the microcoil and the conduit are disposed on a substrate.
87. The method of claim 81 , wherein the microcoil and the conduit are disposed on a ceramic substrate.
88. The method of claim 81 , wherein the microcoil and the conduit are disposed on a chip.
89. The method of claim 71 , wherein the fluid comprises an aqueous fluid.
90. The method of claim 71 , wherein the fluid is optically unclear.
91. The method of claim 71 , wherein the object is a chemical object and/or a biological object.
92. The method of claim 71 , wherein the object is dilute relative to the fluid.
93. The method of claim 71 , wherein the at least one magnetically-labeled object comprises an object labeled via at least one paramagnetic nanoparticle.
94. The method of claim 71 , wherein the NMR detection comprises identification of the at least one magnetically-labeled object.
95. The method of claim 71 , wherein the NMR detection comprises determination of a presence or an absence of the at least one magnetically-labeled object.
96. The method of claim 71 , wherein the NMR detection comprises relaxation time detection.
97. The method of claim 71 , wherein the NMR detection comprises spectroscopy.
98. The method of claim 71 , wherein the NMR detection comprises continuous detection.
99. The method of claim 71 , wherein the frequency is 44.2 MHz or less.
100. The method of claim 71 , wherein the microcoil has an inductance of 93 nH or less.
101. The method of claim 71 , further comprising tuning the microcoil to resonance at the frequency.
102. The method of claim 101 , wherein the tuning comprises providing an input impedance for the electrical circuit.
103. The method of claim 101 , wherein the tuning comprises transforming the impedance of the microcoil.
104. The method of claim 101 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises capacitors.
105. The method of claim 101 , wherein the tuning is via an electrical circuit comprising the microcoil and a tuning circuit that comprises an inductor.