Magnetic coupling high resolution nuclear magnetic resolution probe and method of use

Patent metadata

Field	Value
Publication number	US-10241063-B2
Application number	US-201615325425-A
Country	US
Kind code	B2
Filing date	Apr 8, 2016
Priority date	Apr 15, 2015
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

In an embodiment of the invention inductive coupling of an idler coil to a parent coil is used to provide a double resonance circuit without the disadvantages of capacitive coupling to the parent coil. In an embodiment of the invention, an inductive coupling coil can be used to achieve a double-tuned circuit. In an embodiment of the invention, a circuit uses inductive coupling to achieve a double resonance circuit for 1H, 19F, and 13C experiments where one of the three nuclei are observed and the other two are decoupled. In an embodiment of the invention a pivot or a shunt can be used to couple and decouple the idler coil and the parent coil.

First claim

What is claimed is:

1. A method to simultaneously obtain a Nuclear Magnetic Resonance (NMR) spectrum of two or more nuclei from a sample, comprising:
(a) introducing one or more of a homogeneous or heterogeneous liquid, gas or solid sample into a NMR probe comprising:
(i) a parent coil circuit including a parent coil within the NMR probe;
(ii) one or more elements selected from the group consisting of a pivot, a shunt and a screen; and
(iii) an idler coil circuit including an idler coil;

(b) introducing the NMR probe into a magnetic field;
(c) exciting the sample with a Radio Frequency (RF) pulse at a Larmor frequency;
(d) physically moving the idler coil and/or the screen using the pivot and/or the shunt to inductively couple or decouple the idler coil from the parent coil;
(e) splitting of a resonance of the parent coil circuit into a first mode and a second mode, where moving the idler coil in step (d) adjusts the coupling constant from zero to a non zero value to split the resonance into the first mode and the second mode; and
(f) detecting the NMR spectrum including the first mode and the second mode.

2. The method of claim 1 , where the first mode is detected simultaneously with second mode.

3. The method of claim 1 , further comprising obtaining a NMR spectrum of the sample.

4. The method of claim 1 , where the first mode is 1 H and the second mode is 19 F.

5. The method of claim 1 , where the idler coil circuit includes capacitor C 1 and inductor L 1 and the parent coil circuit includes capacitor C 2 and inductor L 2 , further comprising resonating L 1 and L 2 at a point approximately halfway between the first mode and the second mode using C 1 and C 2 .

6. The method of claim 5 , where C 1 and C 2 are adjusted to split the resonance into the first mode and the second mode.

7. The method of claim 5 , where a coupling constant (k) between the parent coil and the idler coil is given by k=M/√(L 1 L 2 ), where M is the mutual inductance between L 1 and L 2 .

8. The method of claim 1 , where rotation around the pivot moves the idler coil into an orthogonal position relative to the parent coil.

9. The method of claim 1 , where the idler coil is rotated out of an orthogonal position relative to the parent coil to couple the idler coil with the parent coil.

10. The method of claim 1 , further comprising using the shunt to translate the idler coil away from the parent coil to one or both couple and decouple the idler coil from the parent coil.

11. The method of claim 1 , further comprising using the shunt to move the idler coil away from the parent coil to one or both couple and decouple the idler coil from the parent coil.

12. A probe comprising:
(a) a high resolution Nuclear Magnetic Resonance (NMR) probe containing one or more of a homogeneous or heterogeneous liquid, gas or solid sample;
(b) a parent coil circuit including a parent coil and an inductor L 2 ;
(c) one or more elements selected from the group consisting of a pivot, a shunt and a metallic screen; and
(d) an idler coil circuit including an idler coil and an inductor L 1 adapted to allow splitting of a resonance of the parent coil circuit into a first mode and a second mode, where the pivot and/or the shunt are adapted to physically move the idler coil and/or the metallic screen to one or both inductively couple and decouple the idler coil from the parent coil where the coupling constant (k) between the parent coil and idler coil is given by k=M/√(L 1 L 2 ), where M is the mutual inductance between L 1 and L 2 , where physically moving the idler coil and/or the metallic screen adjusts the coupling constant from zero to a non zero value to split the resonance into the first mode and the second mode.

13. The probe of claim 12 , further comprising a pulse generator adapted to apply a RF frequency pulse to the parent coil to one or both couple and decouple the idler coil and the parent coil.

14. The method of claim 1 , where the first mode and the second mode are detected simultaneously.

15. A method comprising:
(a) introducing a sample in an NMR probe into a magnetic field, the NMR probe comprising:
(i) a parent coil circuit including a parent coil and an inductor L 2 ;
(ii) one or more elements selected from the group consisting of a pivot, a shunt and a metallic screen; and
(iii) an idler coil circuit including an idler coil and an inductor L 1 ;

(b) exciting the sample with a Radio Frequency (RF) pulse at a Larmor frequency to generate a resonance;
(c) physically moving the idler coil and/or the metallic screen-using the pivot and/or the shunt to inductively couple and/or decouple the idler coil from the parent coil to allow splitting of the resonance of the parent coil, where the coupling constant (k) between the parent coil and idler coil is given by k=M/√(L 1 L 2 ), where M is the mutual inductance between L 1 and L 2 , where physically moving the idler coil and/or the metallic screen adjusts the coupling constant from zero to a non zero value to split the resonance; and
(d) inductive coupling splitting the resonance of the parent coil circuit into a first mode and a second mode.

16. The method of claim 15 , further comprising undertaking an operation selected from the group consisting of:
(i) detecting the first mode simultaneously with the second mode;
(ii) decoupling the first mode simultaneously from the second mode;
(iii) decoupling the first mode and detecting the second mode; and
(iv) decoupling the second mode and detecting the first mode.

17. The method of claim 16 , further comprising obtaining a NMR spectrum of the sample.

18. The method of claim 16 , where the first mode is 1 H and the second mode is 19 F.

19. The method of claim 18 , where the idler coil circuit includes capacitor C 1 and the parent coil circuit includes capacitor C 2 , further comprising resonating L 1 and L 2 at a point approximately halfway between the first mode and the second mode using C 1 and C 2 .

20. The method of claim 19 , where C 1 and C 2 are adjusted to split the resonance into the first mode and the second mode.

Assignees

• Jeol Ltd

Inventors

• Zens Albert

Classifications

• G01R33/3642

  Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification · CPC title

• G01R33/3635 Primary

  Multi-frequency operation · CPC title

• G01R33/34092

  RF coils specially adapted for NMR spectrometers · CPC title

• G01R33/4616

  using specific RF pulses or specific modulation schemes, e.g. stochastic excitation, adiabatic RF pulses, composite pulses, binomial pulses, Shinnar-le-Roux pulses, spectrally selective pulses not being used for spatial selection · CPC title

• G01N24/08 Primary

  by using nuclear magnetic resonance (G01N24/12 takes precedence) · CPC title