The 5,5-dimethyloxazolidine-2[14C],4-dione distribution technique and the measurement of intracellular pH in Acer pseudoplatanus cells.

The intracellular pH of suspension-cultured Acer pseudoplatanus cells, was estimated from the distribution of 5,5-dimethyloxazolidine-2[14C],4-dione (DMO) between the culture medium and the cells. The metabolization of DMO in this biological system introduces an error in the calculated intracellular pH value. Three methods are given to overcome this difficulty and to estimate the equilibrium between intracellular and extracellular DMO molecules. A preliminary study has shown that the intracellular pH remains constant about 6.5 when the extracellular pH increases from 5.6 to 7.3.