Reverse micelles of dipalmitoyl phosphatidyl choline in chloroform and their interactions with dapsone

1H NMR studies of DiPalmitoyl Phosphatidyl Choline (DPPC) in CDCl3 at various concentrations indicate that DPPC exists as reverse micelles for concentrations beyond 6 mM. The chemical environments of the two acyl chains of DPPC are inequivalent and the inequivalence decreases with increasing DPPC concentration. At low concentrations of DPPC (less than 1.0 mM) intramolecular interactions predominate, whereas at high concentrations, intermolecular interactions predominate. Addition of water to this system, at high concentrations of the phospholipid, reduces the intermolecular interactions. In the presence of the antileprotic drug, Diamino Diphenyl Sulfone (DDS or Dapsone), significant shifts were observed only in the choline resonances of DPPC and the amino resonance of the drug, showing that the amino group of DDS interacts with the head group of DPPC.