Determination of acid dissociation constants and reaction kinetics of dimethylamine-based PPCPs with O, NaClO, ClO and KMnO.

Dimethylamine-based pharmaceutical personal care products (DMA-based PPCPs) are a group of N-nitrosodimethylamine (NDMA) precursors. The acid dissociation constant (pKa) values of four DMA-based PPCPs were determined by potentiometric titration over the pH range of 3-11. The pKa values of ranitidine, nizatidine, doxylamine and carbinoxamine corresponding to the DMA moiety were 8.