31P NMR of mammalian cells encapsulated in alginate gels utilizing a new phosphate-free perfusion medium.

A simple technique permitting long term 31P magnetic resonance spectroscopy of cultured mammalian cells is described. Cells are encapsulated in calcium alginate gels and perfused with a new phosphate-fre medium designed for maintenance of high cell viability. Intracellular pH and beta-NTP/Pi ratios, studied in three cell types, remained stable over a 16-20 h NMR monitoring period. The techniques described may be useful for monitoring cell metabolism with a variety of cell types.