Bergström L Magnus, Bastardo Luis A, Garamus Vasil M
Department of Pharmacy, Pharmaceutical Physical Chemistry, Box 580, Uppsala University, SE-751 23 Uppsala, Sweden.
J Phys Chem B. 2005 Jun 30;109(25):12387-93. doi: 10.1021/jp051113d.
The size and shape of micelles formed in aqueous mixtures of the anionic surfactant sodium dodecyl sulfate (SDS) and the nonionic sugar-based surfactant n-decyl beta-D-glucopyranoside (C(10)G) at different concentrations of added salt have been investigated with small-angle neutron and static light scattering. Rather small prolate ellipsoidal micelles form in the absence of added salt and at [NaCl] = 10 mM in D(2)O. The micelles grow considerably in length to large rods as the electrolyte concentration is raised to [NaCl] = 0.1 M. In excess of nonionic surfactant ([SDS]/[C(10)G] = 1:3) at [NaCl] = 0.1 M in D(2)O, several thousands of Angstroms long wormlike micelles are observed. Most interestingly, a conspicuously large isotope solvent effect was observed from static light scattering data according to which micelles formed at [SDS]/[C(10)G] = 1:3 and [NaCl] = 0.1 M in H(2)O are at least five times smaller than micelles formed in the corresponding samples in D(2)O.
通过小角中子散射和静态光散射研究了在不同添加盐浓度下，阴离子表面活性剂十二烷基硫酸钠（SDS）与非离子糖基表面活性剂正癸基-β-D-吡喃葡萄糖苷（C(10)G）的水性混合物中形成的胶束的大小和形状。在未添加盐以及重水（D₂O）中氯化钠浓度为10 mM时，形成相当小的长椭球形胶束。随着电解质浓度提高到氯化钠浓度为0.1 M，胶束长度大幅增长成为大棒状。在重水（D₂O）中氯化钠浓度为0.1 M且非离子表面活性剂过量（[SDS]/[C(10)G] = 1:3）时，观察到数千埃长的蠕虫状胶束。最有趣的是，根据静态光散射数据观察到显著的大同位素溶剂效应，即在水中[SDS]/[C(10)G] = 1:3且氯化钠浓度为0.1 M时形成的胶束比在相应重水（D₂O）样品中形成的胶束至少小五倍。
