Small scale nmr spectroscopic apparatus and method

Abstract

A magnet assembly for a small scale NMR spectroscopy apparatus suitable for laboratory or home use, generally comprising two permanent magnets facing one another so that the facing surfaces have opposite polarities, a pole cap on each of the two facing surfaces of the permanent magnets, and a plurality of radially polarized canceling magnets disposed about the permanent magnets and pole caps. The design and position of the radially polarized canceling magnets about the tapered pole caps reduces leakage of the magnetic field, to maintain the magnetic field strength and homogeneity within the test region, without a disadvantageous increase in the size, weight and cost of the NMR apparatus. A curved edge ring shim may be used to increase magnetic field homogeneity in the test region. Also provided is a method for measurement of glucose concentration in a fluid using NMR spectroscopy. In one aspect of the invention the fluid is a patient's body fluid and the invention provides for in vivo measurement of the glucose concentration. The method comprises spectral editing in which a RF pulse sequence is used to isolate desired resonances of glucose and thereby facilitate resolution of the glucose signal.