Study of the state of water in the cells of Nitella mucronata using nuclear magnetic resonance

On the basis of measurement of skin-spin and spin-lattice relaxation times of the protons the authors have studied the state of water in the cell of Nitella mucronata. They found two fractions of water in the cell. About 70 per cent cell water content is characterized by long relaxation times (T₁ = 600, T₂ = 300 msec) and the time of exchange with the hydrate sphere of the macromolecules ~0·06 msec. This fraction of water passes into an ice-type state at -8 °C. About 30 per cent of the cell water has short relaxation times (T₁ = 100, T₂ = 50 msec) and no exchange with the hydrate sheath of the macromolecules is noted, while the fraction does not pass into the ice-type state even at -30 °C. It may be concluded that the greater part of the cell water has the properties of "free" and the smaller those of "bound" water.