High-resolution (1)H NMR spectroscopy in organs and tissues using slow magic angle spinning

It is shown that high-resolution (1)H NMR spectra of intact excised tissues and organs can be obtained by rotating the sample slowly about an axis at the magic angle of 54 degrees 44' with the external magnetic field. In this way tissue and cellular damage invoked by standard magic angle spinning (MAS) experiments, where spinning speeds of several kHz are typically employed, are minimized. Special RF pulse sequences, developed originally in solid state NMR, can be used to produce a spinning sideband-free isotropic spectrum. In this article the first results are shown of the brain, heart, liver, gluteus muscle, and kidney excised from mice using the 2D-phase-altered spinning sidebands (PASS) technique and employing MAS spinning speeds of 43-125 Hz. It was found that with slow sample spinning similar, and in some cases even better, spectral resolutions are obtained as compared with fast MAS.