Microcoil based micro-NMR spectrometer and method

• US 6,097,188 A
• Filed: 01/31/1995
• Issued: 08/01/2000
• Est. Priority Date: 01/31/1995
• Status: Expired due to Term

• Current Assignee: University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Sweedler, Jonathan V., Magin, Richard L., Peck, Timothy L., Webb, Andrew G.
• Primary Examiner(s): Arana, Louis
• Assistant Examiner(s): HAYNES, MACK NELSON
• Application Number:
  US08/381,230
• Time in Patent Office: 2,009 Days
• Field of Search: 324/318, 324/321, 324/322
• US Class Current: 324/321
• CPC Class Codes: G01R 33/5604 Microscopy; Zooming

Abstract

The present invention provides an NMR apparatus comprising an analyte sample holder having a containment region that holds a volume of less than about 10 microliters of the analyte sample, a microcoil, which encloses the containment region of the analyte sample holder and the analyte sample contained therein, the microcoil having an inside dimension of less than about 1 mm, and the microcoil operatively associated with the analyte sample contained in the containment region of the analyte sample holder such that the microcoil can transmit and/or receive energy from the analyte sample in the containment region of the analyte sample holder, and a magnet having a mass less than about 50 kg, the magnet positioned about the microcoil and the analyte sample in the containment region of the analyte sample holder to provide a static magnetic field in which the microcoil and the analyte sample in the containment region of the analyte sample holder are located, wherein the microcoil and the magnet provide for the obtainment of an NMR spectrum. The present invention also provides a method of analysis and elucidation of the chemical structure of an analyte using NMR, the method comprising providing an analyte sample that has a volume of less than about 10 microliters, enclosing the analyte sample in a microcoil, generating a static magnetic field about the analyte sample using a magnet, transmitting energy to the analyte sample to excite the sample from its equilibrium state to its excited state, detecting the energy emitted from the analyte sample when the sample relaxes from its excited state to its equilibrium state using the microcoil, and analyzing and graphically displaying the detected energy as a time or frequency domain spectrum.

Claims

1. An NMR apparatus for analyzing and elucidating the chemical structure of an analyte sample, the apparatus comprising:

an analyte sample holder having a containment region that holds a volume of less than 1 microliter of the analyte sample;

a microcoil, which encloses the containment region of the analyte sample holder and the analyte sample contained therein, the microcoil having an inside dimension of less than about 1 mm, and the microcoil operatively associated with the analyte sample contained in the containment region of the analyte sample holder such that the microcoil can transmit and/or receive energy from the analyte sample in the containment region of the analyte sample holder; and

a magnet having a mass less than about 50 kg, the magnet positioned about the microcoil and the analyte sample in the containment region of the analyte sample holder to provide a static magnetic field in which the microcoil and the analyte sample in the containment region of the analyte sample holder are located, wherein the microcoil and the magnet provide for the obtainment of an NMR spectrum of the analyte sample in the containment region of the analyte sample holder having a spectral line width resolution of less th an about 0.1 parts per million.

2. The apparatus of claim 1 wherein the magnet has a maximum dimension of less than about 90 cm.

3. The apparatus of claim 1 wherein the microcoil is a multi-turn solenoidal coil.

4. The apparatus of claim 1 wherein the microcoil is a planar, lithographic coil.

5. The apparatus of claim 1 wherein the planar lithographic coil is a multi-layer, multi-turn coil.

6. The apparatus of claim 1 wherein the analyte sample holder is a capillary.

7. The apparatus of claim 1 wherein the magnet is a superconducting magnet.

8. The apparatus of claim 1 wherein the magnet is a permanent magnet.

9. The apparatus of claim 1 wherein the sample holder is connected to or a part of a liquid chromatography system.

10. The apparatus of claim 1 wherein the sample holder is connected to or a part of a capillary electrophoresis system.

11. A method of analysis and elucidation of the chemical structure of an analyte using NMR, the method comprising:

providing an analyte sample that has a volume of less than 1 microliter;

enclosing the analyte sample in a microcoil wherein the inside dimension of the microcoil is less than about 1 mm;

generating a static magnetic field about the analyte sample using a magnet where the mass of the magnet is less than about 50 kg;

detecting energy emitted from the analyte sample; and

analyzing and graphically displaying the detected energy as a time or frequency domain spectrum having a spectral line width resolution of less than about 0.1 parts per million.

12. The method of claim 11 wherein the microcoil is a multi-turn solenoidal coil.

13. The method of claim 11 wherein the microcoil is a planar, lithographic coil.

14. The apparatus of claim 11 wherein the planar lithographic coil is a multi-layer, multi-turn coil.

15. The method of claim 11 wherein the analyte sample is contained in a capillary.

16. The method of claim 11 wherein the magnet is a superconducting magnet.

17. The method of claim 11 wherein the magnet is a permanent magnet.

18. The method of claim 11 wherein the maximum dimension of the magnet is less than about 90 cm.

19. The method of claim 11 wherein the analyte sample is continuously provided by a liquid chromatography system.

20. The method of claim 11 wherein the analyte sample is continuously provided by a capillary electrophoresis system.