Titration of fatty acids in sugar-derived (APG) surfactants: A C-13 NMR study of the effect of headgroup size, chain length, and concentration on fatty acid pKa at a nonionic micellar interface
The pK(a) of a C-13-enriched fatty acid probe, tetradecanoic acid, was investigated in a variety of sugar-derived (APG) surfactants by using C-13 NMR to monitor the chemical environment of the probe during titration with base. There was an increase of approximately 2 pK(a) units for the probe within the micellar systems compared to the value of acetic acid in water. Analysis shows that the interfa
