A proton NMR study on the structure of water of hydration of aqueous micelles

• DOI: 10.1002/bbpc.19890930215
• Publication Date: 2012-07-28T00:31:22Z
• Authors: Monica I. El Seoud; João P. S. Farah; Omar A. El Seoud
• Keywords: Proton NMR

Abstract The chemical shift of water was measured as a function concentration the detergents cetyltrimethylammonium chloride. CTACl; 3‐N‐dodecyl‐N,N‐dimethylammonio‐1‐propanesulfonate, DDAPS; polyoxyethylene (9.5) octylphenyl ether, Triton X‐100, and deuterium content solvent. short chain compound butyltrimethylammonium bromide also studied model for CTACl. Graphs shifts vs. mole fractions solubilizates were linear in all cases slopes used to calculate so called “fractionation factor, ϕ” which can be measure degree structure hydration appropriate species (relative bulk water). calculated ϕ values indicated that ion does not perturb hydrogen bonding solvent (ϕ = 0.99), whereas Stern layer CTACl is more organized than ( 1.06). Zwitterionic DDAPS found enhance structuring marginally 1.02) nonionic surfactant X‐100 has decreasing effect 0.95).