NMR spectroscopy device based on resonance type impedance (IR) sensor and method of NMR spectra acquisition

• US 9,465,089 B2
• Filed: 11/30/2012
• Issued: 10/11/2016
• Est. Priority Date: 12/01/2011
• Status: Active Grant

• Current Assignee: Neovision LLC (Medtronic Plc)
• Original Assignee: Neovision LLC (Medtronic Plc)
• Inventors: Nikolenko, Yury
• Primary Examiner(s): MILLER, DANIEL R
• Application Number:
  US13/690,786
• Publication Number:
  US 20130141095A1
• Time in Patent Office: 1,411 Days
• US Class Current: 1/1
• CPC Class Codes: G01N 24/08 by using nuclear magnetic resonance G01N24/12 takes precedence
• CPC Class Codes: G01R 33/34053 Solenoid coils; Toroidal coils
• CPC Class Codes: G01R 33/341 comprising surface coils
• CPC Class Codes: G01R 33/3808 Magnet assemblies for single-sided MR wherein the magnet assembly is located on one side of a subject only; Magnet assemblies for inside-out MR, e.g. for MR in a borehole or in a blood vessel, or magnet assemblies for fringe-field MR
• CPC Class Codes: G01R 33/383 using permanent magnets
• CPC Class Codes: G01R 33/44 using nuclear magnetic resonance [NMR] G01R33/24, G01R33/62 take precedence

Abstract

Processes and apparatuses are provided for contactless Nuclear magnetic resonance (“NMR”) spectrum acquiring and spectroscopic analysis and/or measuring or monitoring, in-line, in-situ and/or in real time, at least one composition or object under test of one or more solid, liquid, and/or gaseous substances and/or one or more bulk materials. One or more apparatus may include a resonance type impedance sensor having at least two coils, at least one coil of the at least two coils being at least one excitation coil, at least one other coil of the at least two coils being at least one sensing coil. The method(s) involve acquiring an NMR spectrum of an object under test while changing at least one of the frequency of an IR sensor and the intensity of the magnetic field applied to an object under test and/or sweeping intensity of the magnetic field applied to the object under test.

Claims

1. An apparatus for contactless acquiring of a nuclear magnetic resonance (NMR) spectrum of an object under test and analyzing said spectrum in order for (A) detecting (B) measuring or (C) monitoring at least one chemical or biological component of said object under test in real time in-line or in-situ, comprising:

at least one resonance type impedance (IR) sensor which is a multicoil open-core or air-core inductor, said sensor comprising at least two coils, at least one coil of the at least two coils being at least one excitation coil connected to at least one alternating current source with frequency sweep, at least one other coil of the at least two coils being at least one sensing coil connected to at least one data processing system, wherein;

(i) upon electrical connection to said current source, said at least one excitation coil is to propagate electromagnetic energy into said at least one sensing coil to generate a probing electromagnetic field at a Larmor frequency of the at least one chemical or biological component, (ii) said at least one sensing coil having intrinsic inductance L, intrinsic capacitance C, and intrinsic resistance R parameters to provide resonance conditions for measuring said probing electromagnetic energy drain from a resonant circuit represented by said sensing coil, caused by energy dissipation due to Larmor precession around an external magnetic field of a magnetic moment of particles of the at least one chemical or biological component of said object under test or at least a portion of said object under test being disposed within a sensing area of said at least one sensing coil at a predetermined frequency range defined by said Larmor frequency, and (iii) said at least one sensing coil uses only its intrinsic capacitance and is not connected to any capacitance means;

at least one magnetic system providing a constant or variable homogeneous magnetic field;

at least one radio frequency (RF) sweep generator, the at least one RF sweep generator being electrically connected to at least one said excitation coil;

at least one data acquisition block, wherein the at least one data acquisition block is electrically connected to;

(i) at least one said excitation coil, (ii) at least one said sensing coil, or (iii) to both said excitation and sensing coils;

at least one calculation block connected to said;

at least one data acquisition block, at least one magnetic system, and at least one RF sweep generator;

at least one communication block connected to said at least one calculation block and to a computer in order to provide data interchange between said computer and said NMR apparatus; and

at least one power supply electrically connected to said;

at least one RF sweep generator, at least one calculation block, at least one magnetic system and at least one communication block.

2. The apparatus of claim 1, wherein said at least one data acquisition block has high electrical input impedance.

3. The apparatus of claim 2, wherein said at least one data acquisition block has electrical input impedance greater than 10MΩ

or substantially greater than 10MΩ

.

4. The apparatus of claim 1, comprising at least one test fixture for containing samples.

5. The apparatus of claim 4, wherein said test fixture is spun to average any magnetic field variations, as well as said test fixture imperfections.

6. The apparatus of claim 1, wherein said magnetic system comprises at least one of:

(i) at least one electromagnet coil connected to at least one controlled power supply capable to control an intensity of the magnetic field applied to the object under test;

(ii) at least one means to measure the intensity of the magnetic field applied to the object under test;

(iii) at least one electromagnet;

(iv) at least one permanent magnet; and

(v) at least one magnetic conductor.

7. The apparatus of claim 6, wherein said electromagnet coil is located on a magnetic conductor as far as possible from the gap where said object under test is situated in order to reduce and/or minimize distortions of the homogeneous magnetic field made by and/or controlled by said electromagnet coil.

8. The apparatus of claim 6, wherein said magnetic system is transformable and/or convertible such that the magnetic system is capable of changing an intensity of the magnetic field applied to the object under test.

9. The apparatus of claim 6, wherein said at least one magnetic conductor includes a truncated cone section capable of concentrating the magnetic field applied to the object under test.

10. The apparatus of claim 9, wherein at least one of:

(i) said truncated cone section is made of at least one magnetic material;

(ii) said at least one magnetic material has a high permeability and a high saturation level; and

(iii) said high permeability is where relative permeability μ

/μ

_o is substantially equal or more than about 4000 and said high saturation level is substantially equal or more than about 15000 gauss.

11. The apparatus of claim 6, wherein at least one of:

(i) said at least one magnetic conductor is made of at least one magnetic material;

(ii) said at least one magnetic conductor includes an upper movable part and a lower part, the upper movable part and the lower part comprising the at least one magnetic material;

(iii) said at least one magnetic material has a high permeability and a high saturation level; and

(iv) said high permeability is where relative permeability μ

/μ

_o is substantially equal or more than about 4000 and said high saturation level is substantially equal or more than about 15000 gauss.

12. The apparatus of claim 1, wherein said at least one resonance type impedance (IR) sensor comprises at least two resonance type impedance (IR) sensors designed to acquire an NMR signal from different target nuclei.

13. A method of acquiring an NMR spectrum using the apparatus of claim 8, the method comprising:

placing an object under test into the sensing area of said IR sensor;

searching for resonant frequency of said IR sensor;

changing the intensity of the magnetic field applied to the object under test by means of the transformable and/or convertible magnetic system;

measuring the intensity of the magnetic field applied to the object under test;

calculating of Larmor precession frequency;

stopping the changing of the intensity of the magnetic field applied to the object under test when the Larmor precession frequency coincides with, substantially matches, or substantially equals said resonant frequency of said IR sensor; and

acquiring an NMR spectrum of said object under test while changing the frequency of said IR sensor by means of said RF sweep generator electrically connected to said excitation coil.

14. A method of acquiring an NMR spectrum using the apparatus of claim 8, the method comprising:

placing an object under test into the sensing area of said IR sensor;

searching for resonant frequency of said IR sensor;

changing the intensity of the magnetic field applied to the object under test by means of the transformable and/or convertible magnetic system;

measuring the intensity of the magnetic field applied to the object under test;

calculating of Larmor precession frequency;

stopping the changing of the intensity of the magnetic field applied to the object under test when the Larmor precession frequency coincides with, substantially matches, or substantially equals said resonant frequency of said IR sensor; and

acquiring an NMR spectrum of said object under test while changing the intensity of the magnetic field applied to the object under test by means of said at least one electromagnet coil connected to the at least one controlled power supply.

15. A method of acquiring an NMR spectrum using the apparatus of claim 6, the method comprising:

placing an object under test into the sensing area of said IR sensor;

searching for resonant frequency of said IR sensor;

changing the intensity of the magnetic field applied to the object under test by means of said at least one electromagnet coil connected to the at least one controlled power supply;

measuring the intensity of the magnetic field applied to the object under test;

calculating of Larmor precession frequency;

stopping the changing of the intensity of the magnetic field applied to the object under test when the Larmor precession frequency coincides with, substantially matches, or substantially equals said resonant frequency of said IR sensor; and

acquiring of an NMR spectrum of said object under test while changing the frequency of said IR sensor by means of said RF sweep generator electrically connected to said excitation coil.

16. A method of acquiring an NMR spectrum using the apparatus of claim 6, the method comprising:

placing an object under test into the sensing area of said IR sensor;

searching for resonant frequency of said IR sensor;

changing the intensity of the magnetic field applied to the object under test by means of said at least one electromagnet coil connected to the at least one controlled power supply;

measuring the intensity of the magnetic field applied to the object under test;

calculating of Larmor precession frequency;

stopping the changing of the intensity of the magnetic field applied to the object under test when the Larmor precession frequency coincides with, substantially matches, or substantially equals said resonant frequency of said IR sensor; and

acquiring of an NMR spectrum of said object under test by sweeping intensity of the magnetic field applied to the object under test by means of said at least one electromagnet coil connected to the at least one controlled power supply, the sweeping occurring in a vicinity of the intensity of the magnetic field found in the stopping the changing of the intensity step.