Characterization of clusters interaction sites at cluster of sodium dodecyl sulfate and water soluble noniomic macromolecules investigated by 1H NMR, 13C NMR and 2D NMR

Clusters Interaction sites at the clusters of sodium dodecyl sulfate (SDS) and polyethylene glycol (PEG) and SDS-polyvinylpyrrolidone (PVP) were investigated by means of H-1 NMR, C-13 NMR, 2D NOESY-NMR and 2DROESY-NMR. The experimental results show that in SDS-PVP cluster, the interaction signal between C1 and C2 methylenes close to hydrophobic tail of SDS and the main chain alpha-C, carbonyl C1 segment (P-1) and C4 methylene (P-4) of the pentatomic ring around the central lactam N atom of PVP was very strong, which suggests that the probable interaction sites between PVP and the bound micelle of SDS are the hydrophilic head of SDS with the lactam N atom of PVP and the adjacent atoms of both molecules. Also in SDS-PEG cluster, besides the interaction of polar sections' between SDS and PVP, some of PEG chains penetrate into the area nearby the C-3 or deeper inside the bound micelle of SDS.