[Proton magnetic relaxation time of normal and tumor cells]

A proton NMR analysis of an in vitro culture of cells in heavy water has been made. The relaxation times of L-strain cells 929, He-La, transformed and normal embryonic human cells, C3H mice and isolated Yoshida sarcoma tumour cells, as well as of Yoshida sarcoma tumour tissue were determined. It turned out that spin-lattice (T1) and spin-spin (T2) relaxation times are characteristic of every cell and fairly different from those of corresponding tissues, which may be used for NMR identification of cells (NMR cytology). Furthermore, it has incontestably been proved that there is an ordered water fraction of cells, which is very slowly exchanged with surrounding heavy water.