GRADIENT, HIGH-RESOLUTION, MAGIC-ANGLE-SPINNING H-1 NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY OF INTACT-CELLS

The application of new gradient, high-resolution, magic angle spinning (MAS) H-1 nuclear magnetic resonance (NMR) spectroscopy to the study of intact undifferentiated and differentiated NIH 3T3 F442A cells demo nstrated improved spectral resolution and sensitivity compared with st atic studies. MAS of cells permits the detection and quantitation of m any cellular metabolites that are not clearly resolved in nonspinning measurements and provides an improved visibility of phospholipids. Gra dient, MAS enables the use of diffusion weighting for compartment assi gnment and the determination of mobility for many metabolites which ar e incompletely resolved using static techniques, The smaller, undiffer entiated preadipocytes show no microscopic evidence of cell lysis afte r 2 h of MAS at 3.5 kHz and 82% of these cells remain viable by trypan blue exclusion, In contrast, 15-19% of the larger, lipid-laden differ entiated adipocytes were found to suffer some degree of cell lysis wit h MAS, This new method is an attractive alternative to either nonspinn ing perfusion or extraction techniques for NMR studies of cells.