Anion-Specific Binding to <i>n</i>-Hexadecyl Phosphorylcholine Micelles
作者:Jacks P. Priebe、Bruno S. Souza、Gustavo A. Micke、Ana C. O. Costa、Haidi D. Fiedler、Clifford A. Bunton、Faruk Nome
DOI:10.1021/la902469d
日期:2010.1.19
ion incorporation in the micellar pseudophase parallels the increase in the negative zeta potential, and salts increase the rate of A1 hydrolysis of 2-(p-heptyloxyphenyl)-1,3-dioxolane in micellized HPC and inhibit the reaction of OH− with naphthoic anhydride. The kinetic effects are larger with NaClO4 than with NaCl. The increased micellar negative charge with added salts increases the repulsion between
Synthesis of a New Zwitterionic Surfactant Containing an Imidazolium Ring. Evaluating the Chameleon-like Behavior of Zwitterionic Micelles
作者:Daniel W. Tondo、Elder C. Leopoldino、Bruno S. Souza、Gustavo A. Micke、Ana C. O. Costa、Haidi D. Fiedler、Clifford A. Bunton、Faruk Nome
DOI:10.1021/la102391e
日期:2010.10.19
Synthesis of a new zwitterionic surfactant containing the imidazolium ring 3-(1-tetradecyl-3-imidazolio)propane-sulfonate (ImS3-14) is described. The solubility of ImS3-14 is very low but increases on addition of a salt which helps to stabilize the micellized surfactant. Fluorescence quenching and electrophoretic evidence for ImS3-14 shows that the micellar aggregation number is only slightly sensitive to added salts, as is the critical micelle concentration, but NaClO4 markedly increases zeta potentials of ImS3-14 in a similar way as in N-tetradecyl-N,N-dimethylammonio-1-propane-sulfonate (SB3-14) micelles. The rate of specific hydrogen ion catalyzed hydrolysis of 2-(p-heptoxyphenyl)-1,3-dioxolane and equilibrium protonation of 1-hydroxy-2-naphthoate ion in zwitterionic micelles of ImS3-14 and SB3-14 are increased markedly by NaClO4 which induces anionoid character and uptake of H3O+, but NaCl is much less effective in this respect. Comparison of ImS3-14 with SB3-14 is based on experimental evidence, and computational calculations indicate similarities and differences in structures of both compounds.