Figure 2.

DOSY analysis of mSBF. (a) Mapped diffusion coefficients in dependence of the chemical shift. When both the P_i and the P_PNS signals, appear well-separated in the ³¹P NMR spectra, DOSY of the system allows one to discern two phosphate species via their diffusion coefficients. A slower diffusion coefficient is observed for the species underlying P_PNS (left) compared to the signal underlying P_i (right). The diffusion coefficients were ∼24 × 10^–10 vs ∼43 × 10^–10 m² s^–1, respectively. The data were acquired at 37 °C for 5 h at a phosphate concentration of 5 mM. (b) Monoexponential fits of the two DOSY profiles underlying the data in panel (a). The P_PNS signal decays slower with increasing gradient amplitude than the P_i signal.