A ³¹P nuclear magnetic resonance (NMR) method has been established to noninvasively measure intracellular condition of Hela cell, stable ³¹P NMR spectra of living cells were obtained and intracellular metabolite in Hela of phosphorized small molecule cell was analyzed. The chemical shift of intracellular inorganic phosphate (Pi) ,which is very sensitive to cytosolic pH, can be shifted on the ³¹P NMR spectrum as pH is changed and cytosolic pH can be derived from chemical shift of Pi peak. Intracellular pH 7.05±0.01 was calculated based on the chemical shift of Pi peak (5.88±0.01) in Hela cells．Based upon a measurement of chemical shift differences between the α and β-phosphoryl resonances in the ³¹P NMR spectrum of intracellular adenosine triphosphate (ATP) in Hela cell, the fraction of total ATP complexed to Mg^2＋was estimated, while cytosolic free magnesium ion concentration in Hela cells was measured nondestructively to be 253.3 mmol/L. ³¹P nuclear magnetic resonance method has noninvasive virtue in measuring intracellular Mg^2＋ compared with other technique.

Key words: ³¹P NMR, Hela cell, chemical shift, free magnesium