Temperature calibration of a high-resolution magic-angle spinning NMR probe for analysis of tissue samples

The increase in tissue sample temperature caused by the spinning of a rotor in high-resolution magic-angle spinning (HRMAS) NMR spectroscopy was inves tigated using two literature NMR thermometers. The classical methanol therm ometer was used to calibrate the temperature difference between the set tem perature and the actual sample temperature. At spin speeds of 2, 4, 6 and 8 kHz, a mean increase in sample temperature over the set temperature of 0.8 +/- 0.1, 2.2 +/- 0.1, 5.0 +/- 0.1 and 7.9 +/- 0.2 K, respectively, was not ed. This calibration was used to gauge the accuracy of the literature gluco se thermometer, which was shown to have a mean increase over the set temper ature of -0.3 +/- 0.1, 1.2 +/- 0.2,3.0 +/- 0.2 and 6.1 +/- 0.1 K at 2, 4, 6 and 8 kHz, respectively. By correcting for the errors measured in this stu dy, a more accurate determination and adjustment of sample temperature in H RMAS NMR spectroscopic analyses of intact tissues is now possible. Copyrigh t (C) 2001 John Wiley & Sons, Ltd.