HYDROPHOBIC AND POLAR CONTRIBUTIONS TO SOLUTE AFFINITY FOR A HIGHLY CROSSLINKED WATER-SWOLLEN (SEPHADEX) GEL
HYDROPHOBIC AND POLAR CONTRIBUTIONS TO SOLUTE AFFINITY FOR A HIGHLY CROSSLINKED WATER-SWOLLEN (SEPHADEX) GEL
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DOI：
10.1002/pol.1980.130180406
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发表时间：
1980-01-01
期刊：
影响因子：
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通讯作者：
MARSDEN, NVB
中科院分区：
文献类型：
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作者：
HAGLUND, AC;MARSDEN, NVB
葡聚糖 (Sephadex) 凝胶由 Porath 和 Flodin 于 1959 年首次推出 (l)，因其分子筛特性及其在凝胶过滤中的应用而闻名 (2)。然而，凝胶-溶质相互作用可能会深刻地影响溶质分配，特别是在更高交联的形式中，尽管后者也可以本质上充当针对某些溶质（例如寡糖）的分子筛（3）。然而，这些凝胶中溶质分配所涉及的机制尚不清楚。当在水中溶胀时，高度交联但未取代的葡聚糖凝胶对许多芳香族化合物 (43) 以及弱极性脂肪族溶质 (6) 具有亲和力。人们对前者的渴望往往相当大，并且出现了特殊芳香亲和力的概念 (7)。对极性较小的脂肪族溶质的亲和力表现出疏水相互作用的多种特性 (8)。因此，它似乎是一个熵主导的过程 (8)，需要水 (9) 的存在，并且它会被所谓的水结构扰动物（如尿素和胍盐 (10)）以与它们影响非离子表面活性剂形成胶束的趋势相同的方向改变 (1 1, 12)。 bic 相互作用在非极性和弱极性脂肪族溶质的吸附中，（b）表明溶质中的 n 电子促进亲和力，（c）表明石蜡羟基衍生物中亲和力的降低是由于 OH 基团的极性导致疏水性降低而引起的，（d）表明如果要表现出分子筛行为，则对溶质结构有严格的要求，并且（e）表明，而凝胶对脂肪族和芳香族烃具有亲和力，它不喜欢后者；更高的芳香族亲和力需要额外的条件。
The dextran (Sephadex) gels, fist introduced by Porath and Flodin in 1959 (l), are best known for their molecular sieve properties and their use in gel fitration (2). Gel-solute interactions, however, may profoundly affect solute partitioning, particularly in the more highly crosslinked forms although the latter can also act essentially as molecular sieves towards some solutes, eg, oligosaccharides (3). The mechanisms involved in solute partitioning in these gels are, however, not well understood. When swollen in water, highly crosslinked, but otherwise unsubstituted, dextran gels have an affinity for many aromatic compounds (43) and also for weakly polar aliphatic solutes (6). The avidity for the former is often considerable and the concept of a special aromatic affinity has emerged (7). The affinity for less polar aliphatic solutes exhibits several properties characteristic of hydrophobic interactions (8). Thus, it appears to be an entropy-dominated process (8), requiring the presence of water (9) and it is changed by so-called water structure perturbants such as urea and guanidinium salts (10) in the same direction as they affect the tendency of a nonionic surfactant to form micelles (1 1, 12). bic interaction in the adsorption of nonpolar and weakly polar aliphatic solutes,(b) suggest that n electrons in the solute promote affinity,(c) suggest that a reduced affinity in hydroxyl derivatives of paraffins is caused by lowered hydrophobicity due to the polarity of the OH group,(d) show that there are stringent demands on solute structure if molecular sieve behavior is to be manifest, and (e) show that, whereas the gel has an affinity for hydrocarbons, both aliphatic and aromatic, it does not prefer the latter; a higher aromatic affinity requires an additional condition.