Magnetic detector

• US 9,234,877 B2
• Filed: 03/13/2013
• Issued: 01/12/2016
• Est. Priority Date: 03/13/2013
• Status: Active Grant

• Current Assignee: Endomagnetics Ltd., University of Houston (University of Houston System)
• Original Assignee: Endomagnetics Ltd., University of Houston (University of Houston System)
• Inventors: Hattersley, Simon Richard, Laitenberger, Peter Georg, Brazdeikis, Audrius
• Primary Examiner(s): Nguyen, Tung X
• Assistant Examiner(s): SHAH, NEEL D
• Application Number:
  US13/799,334
• Publication Number:
  US 20140266174A1
• Time in Patent Office: 1,035 Days
• Field of Search: 324/232, 324243-244, 600/10, 600/12, 600/17, 600/310, 600/409, 600/411, 600/417, 600/424, 600/420, 600/443
• US Class Current: 1/1
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: G01N 27/72 by investigating magnetic variables
• CPC Class Codes: G01N 27/745 for detecting magnetic beads used in biochemical assays concerning the assays G01N33/54326; sensors therefor G01R33/1269; automatic analysers therefor G01N35/0098
• CPC Class Codes: G01R 33/0213 using deviation of charged particles by the magnetic field
• CPC Class Codes: G01R 33/10 Plotting field distribution ; Measuring field distribution
• CPC Class Codes: G01R 33/1276 of magnetic particles, e.g. imaging of magnetic nanoparticles G01R33/1269 takes precedence

Abstract

A probe for detecting magnetic particles. In one embodiment, the probe includes: a cylindrical probe core having a first end and a second end, the cylindrical probe core defining two channels for containing coils of wire, one of the channels being adjacent the first end of the cylindrical probe core; two sense coils, one each of the sense coils being located in a respective one of the channels; and two drive coils, one each of the drive coils being co-located with the respective sense coil in a respective one of the channels.

Claims

1. A handheld magnetic susceptometry probe for detecting a magnetic marker within a body comprising:

a probe core having a first end and a second end, the probe core defining two longitudinal regions for containing coils of wire, one of the regions being adjacent the first end of the cylindrical probe core;

two sense coils, one each of the sense coils being located in a respective one of the regions; and

two drive coils, one each of the drive coils being located in a respective one of the regions, wherein the regions are longitudinally separated by a distance equal to or greater than the diameter of one of the coils, wherein the drive coil and the sense coil in each region are in close proximity.

2. The probe of claim 1 wherein the magnetic marker comprises magnetic nanoparticles.

3. The probe of claim 1 wherein one of the set of two drive coils and the set of two sense coils is connected as a gradiometer, and the other of the set of two drive coils and the set of two sense coils is connected in series.

4. The probe of claim 3 wherein the sense coils and the drive coils have different diameters, and the diameter of the sense coils is greater than the diameter of the drive coils.

5. The probe of claim 4 wherein the sense coils and the drive coils have different diameters the diameter of the largest coil is less than 15 mm.

6. The probe of claim 4 wherein the wire of the drive coils have different numbers of turns has a larger gauge than the wire of the sense coils.

7. The probe of claim 4 wherein the sense coils and the drive coils have different numbers of turns.

8. The probe of claim 1:

wherein the regions of the probe core define two channels for containing coils of wire, one of the channels being adjacent the first end of the cylindrical probe core,

wherein one each of the sense coils being located in a respective one of the channels,

wherein one each of the drive coils being co-located with the respective sense coil in a respective one of the channels,

wherein the drive coils are connected in series, and

wherein the sense coils are connected in anti-series.

9. The probe of claim 1 wherein the drive coil is wound on top of the sense coil.

10. The probe of claim 1:

wherein the regions of the probe core define two channels for containing coils of wire, one of the channels being adjacent the first end of the cylindrical probe core,

wherein one each of the sense coils being located in a respective one of the channels,

wherein one each of the drive coils being co-located with the respective sense coil in a respective one of the channels,

wherein the drive coils are connected in anti-series, and

wherein the sense coils are connected in series.

11. The probe of claim 1 further comprising:

a third drive coil, the third drive coil in series connection between the first and the second drive coil and positioned between the first and second drive coil so as to form a single solenoidal drive coil,

wherein one each of the sense coils being located near a respective end of the single solenoidal drive coil.

12. The probe of claim 11 wherein every turn of the single solenoidal drive coil is of the same diameter.

13. The probe of claim 11 wherein turns in the longitudinal center of the single solenoidal drive coil have a greater diameter than turns on the ends.

14. The probe of claim 11 wherein every turn of the single solenoidal drive coil is of the same spacing.

15. The probe of claim 11 wherein turns in the longitudinal center of the single solenoidal drive coil have a greater spacing than turns on the ends.

16. The probe of claim 1 wherein the probe core comprises a material with a thermal diffusivity of substantially ≧

20×

10<sup>−

6</sup> m²/s wherein thermal diffusivity is defined as (Thermal conductivity/{Density×

Specific heat capacity}).

17. The probe of claim 1 wherein the probe core comprises a material with a toughness G_ic of greater than 9×

10<sup>−

3</sup> KJm<sup>−

2</sup>, wherein toughness is defined as {Fracture toughness, K_ic}²/Young'"'"'s Modulus.

18. The probe of claim 17 wherein the probe core comprises a ceramic selected from the group consisting of boron nitride, aluminium nitride, silicon carbide, Shapal-M, Macor and combinations thereof.