NMR investigation of counterion binding to undecyl LL-leucinevalanate micelles
NMR investigation of counterion binding to undecyl LL-leucinevalanate micelles
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抗衡离子与十一烷基 LL-亮氨酸戊酸胶束结合的 NMR 研究
DOI：
10.1080/01932691.2022.2145303
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发表时间：
2022
影响因子：
2.2
通讯作者：
Morris, Kevin F.
中科院分区：
文献类型：
--
作者：
Fletcher, Jessica;Mahant, Grant;Witzleb, Tyler;Busche, Riley;Garcia, Mauro;Fang, Yayin;Billiot, Eugene J.;Billiot, Fereshteh H.;Morris, Kevin F.
用核磁共振波谱研究了阳离子反离子与十一烷基亮氨酸丁二醇酯形成的阴离子胶束的结合。以氨基酸为基础的表面活性剂，如und-LV，是商业表面活性剂的绿色替代品。单体和聚合形式的und-LV胶束也被用作毛细管电泳手性选择剂。考察的反离子有Na+、四乙基铵离子、L赖氨酸、1，4-二氨基丁烷、1，6-二氨基己烷以及1，2-二氨基环己烷和1，4-二氨基环己烷的顺式和反式异构体。反离子和胶束扩散系数的核磁共振测量被用来计算胶束半径和与胶束结合的反离子分子的摩尔分数。用二维核磁共振实验研究了反离子胶束络合物的结构。在含有Na+或四乙基铵反离子的溶液中，结合反离子的摩尔分数不随pH变化。然而，对于所有其他反离子，当反离子带有 + 1或+2时，胶束结合的反离子的摩尔分数在pH 10以下较高，当反离子为中性或两性离子时，胶束结合的反离子的摩尔分数低于pH 10-10.5。胶束半径随pH值的变化和二维核磁共振实验表明，L赖氨酸、1，4-二氨基丁烷和1，6-二氨基己烷平行结合在胶束表面，其胺类官能团与不同的表面活性剂单体相互作用。相反，二氨基环己烷异构体垂直于胶束表面结合。胶束结合的顺式-1，4-二氨基环己烷和反式-1，4-二氨基环己烷的摩尔分数非常相似。然而，对于1，2-环己二胺，在低pH值下，顺式异构体的胶束结合反离子摩尔分数大于反式异构体。
NMR spectroscopy was used to investigate the binding of cationic counterions to anionic micelles formed by undecyl LL-leucinevalaninate (und-LV). Amino acid-based surfactants like und-LV are green alternatives to commercial surfactants. Monomeric and polymeric forms of und-LV micelles have also been used as chiral selectors in capillary electrophoresis (CE) separations. The counterions investigated were Na+, the tetraethylammonium ion, L-Lysine, 1,4-diaminobutane, 1,6-diaminohexane, and cis and trans isomers of 1,2-diaminocyclohexane and 1,4-diaminocyclohexane. NMR measurements of counterion and micelle diffusion coefficients were used to calculate micelle radii and the mole fraction of counterion molecules bound to the micelles. Two-dimensional NMR experiments were used to investigate the structures of the counterion: micelle complexes. The mole fraction of bound counterions did not change with pH in solutions containing Na+or tetraethylammonium counterions. With all other counterions, however, the mole fraction of micelle-bound counterions was higher below pH 10 when counterions had a + 1 or +2 charge, and lower above pH 10–10.5 when the counterions were neutral or zwitterionic. Changes in micelle radii with pH and two-dimensional NMR experiments suggested that L-Lysine, 1,4-diaminobutane, and 1,6-diaminohexane bound parallel to the micelle surface with their amine functional groups interacting with different surfactant monomers. In contrast, the diaminocyclohexane isomers were found to bind perpendicular to the micelle surface. The mole fractions of micelle-bound cis-1,4-diaminocyclohexane and trans-1,4-diaminocyclohexane were very similar to one another. However, with 1,2-cyclohexanediamine, at low pH the mole fraction of micelle-bound counterions was larger for the cis isomer than for the trans isomer.
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影响因子：
13.6
作者：
Yan T;Feringa BL;Barta K
通讯作者：
Barta K
DOI：
10.4236/ajac.2021.125012
发表时间：
2021-05
期刊：
American Journal of Analytical Chemistry
影响因子：
--
作者：
Mauro Garcia;Amanda Risley;F. Billiot;E. Billiot;K. Morris
通讯作者：
Mauro Garcia;Amanda Risley;F. Billiot;E. Billiot;K. Morris
DOI：
10.1006/jmra.1996.0199
发表时间：
1996-10-01
期刊：
JOURNAL OF MAGNETIC RESONANCE SERIES A
影响因子：
--
作者：
Ammalahti, E;Bardet, M;Cadet, J
通讯作者：
Cadet, J
DOI：
10.2174/138620712798280853
发表时间：
2012-01-01
影响因子：
1.8
作者：
Jeannerat, Damien;Furrer, Julien
通讯作者：
Furrer, Julien
扩散和电泳核磁共振
影响因子：
1.6
作者：
P. Stilbs
通讯作者：
P. Stilbs