Slow magic angle spinning nuclear magnetic resonance device and process for metabolomics profiling of tissues and biofluids
A slow Magic-Angle Spinning NMR device and method are detailed that provide high resolution and high sensitivity metabolic profiling of biological samples. A new 1 H-PASS sequence suppresses line broadening in the various biological samples. The device and method allow metabolic changes in small animals to be tracked through continuous investigations of minimally-invasive blood and tissue biopsy samples over a sustained period and allow intact biological objects with sizes up to a few centimeters to be studied.
1. A slow Magic Angle Spinning (MAS) Nuclear Magnetic Resonance (NMR) device, comprising:
a sample spinning probe configured to rotate a sample inclined at a magic angle with respect to the B 0 magnetic field at a slow spinning rate, the probe includes a rotor with a sample tube adapter configured to hold a sample tube of varied dimensions containing a sample of a variable size, quantity, and/or volume in the rotor when introduced into a support body of the probe; and
a switchable LC resonator comprising a first static RF coil coupled to one or more capacitors that defines an RF circuit, the LC resonator attaches to a switchable plug component that inserts into the support body of the probe, the LC resonator when inserted in the support body inductively couples the first static RF coil with a second static RF coil disposed therein that enhances the sample filling factor between the sample and the first RF coil and the sensitivity of sample analyses therein.
2. The device of claim 1 , wherein the probe is configured to rotate the sample at a slow spinning rate defined below about 500 Hz.
3. The device of claim 1 , wherein the first static RF coil circumvolves the sample tube in the rotor.
4. The device of claim 1 , wherein the switchable LC resonator and first static RF coil are switchable with an LC resonator and static RF coil of a smaller or larger width dimension that accommodate a sample tube with a smaller or larger width dimension in the rotor.
5. The device of claim 1 , wherein the probe includes a single rotation bearing.
6. The device of claim 1 , wherein the probe includes dual rotation bearings.
7. The device of claim 6 , wherein the probe includes a first rotation bearing disposed in the support body in front of the second RF coil where into which the sample tube inserts into the rotor.
8. The device of claim 6 , wherein the probe includes a second rotation bearing disposed at the rear of the second RF coil where the switchable plug attached to the LC resonator and first static RF coil insert into the support body of the probe.
9. The device of claim 1 , wherein the probe includes an optical detection system comprising a first optical detection channel on a support with a first optical fiber that counts and determines spinning rate of the rotor.
10. The device of claim 9 , wherein the first optical fiber determines spinning rate with a selected number of counting marks disposed on a surface of the rotor during rotation thereof.
11. The device of claim 10 , wherein the number of counting marks on the surface of the rotor is a multiple of 6 below and including 24.
12. The device of claim 1 , wherein the optical detection system includes a second optical detection channel on a support with a second optical fiber that synchronizes a slow MAS pulse sequence to a specified rotor position.
13. The device of claim 12 , wherein the second optical fiber synchronizes rotor position with a 1 H Phase Adjusted Spinning Sidebands (PASS) pulse sequence that includes a rotor position synchronization sequence segment therein.
14. The device of claim 13 , wherein the second optical fiber synchronizes the rotor position with optical triggering based on a single fixed mark disposed on a surface of the rotor during rotation of the rotor.
15. The device of claim 13 , wherein the pulse sequence suppresses magnetic susceptibility induced line broadening effects for the sample at the slow spinning rate.
16. The device of claim 13 , wherein the pulse sequence controls timing of pulses delivered by the pulse sequence.
17. The device of claim 1 , wherein the sample tube adapter and/or switchable plug and/or a support of the switchable coil are composed of a machinable plastic.