RELAXATION-TIME MEASUREMENTS OF BULK WATER IN PACKED MAMMALIAN DENSITY-DEPENDENT AND DENSITY-INDEPENDENT CELLS GROWN IN CULTURE

Measurements of T1 and T2 relaxation times of bulk water have been made at 30 MHz for several species of mammalian density-dependent and -independent (transformed) cells grown in culture and packed under controlled conditions. Only one component of relaxation time was resolved in each case. The T1 and T2 values appear to depend primarily on the amount of cellular water, and not to be due to trace paramagnetic metal ions. While the average value of the T1 for the density-independent cells (1.24 ± 0.25 sec, 28 values) was lower than that for the density-dependent cells (1.31 ± 0.31 sec, 18 values) the difference was not significant. Changes in T1 values were also not significant when either class of cell was nonviable or lysed. The T1 and T2 values of the corresponding cell supernatant solutions were always longer (ca. 2.7 sec). © 1979.