Using Sodium Cation Organization To Study the Phase Behavior of Bicelle Solutions

The 2 3 Na nuclear magnetic resonance (NMR) spectra for NaCI dissolved in the nematic phase of dimyristoyl-phosphatidylcholine (DMPC)/dihexanoyl-phosphatidylcholine (DHPC) bicelle solutions at 34 °C display line splittings consistent with the quadrupolar satellite transitions for the I = 2 3 Na nucleus. At temperatures exceeding 40 °C additional residual 2 3 Na satellite transition lines develop, suggesting that a new ordered phase similar to pure DMPC is present.