Ion Binding and Reactivity in Association Colloids

在广泛的表面电荷密度和溶液组成范围内，将开发用于探测缔合胶体和囊泡的界面组成的新方法。聚集体结合疏水芳基重氮盐脱氮的产物分布将提供界面亲核试剂组成的“快照”视图。该探针将同时用于估计水和反离子的界面浓度，以及醇的分布和反离子的选择性。表面电荷密度对反离子结合以及具有磷脂样头基的两性表面活性剂组成的胶束的大小和形状的影响将通过核磁共振、分光光度法和电位法确定。这项来自有机动力学项目的拨款支持了罗格斯大学劳伦斯·s·罗姆斯特德教授的研究。与聚集分子（胶体和囊泡）结合的活性物质（芳基重氮盐）将在聚集-水界面与溶剂和其他分子发生反应，从而获得该界面的“快照”视图。表面电荷密度对骨料和骨料形状的影响将通过采用各种仪器技术来确定。这些研究将有助于更好地理解磷脂酶A2与磷脂囊泡（聚集体）结合的重要生物学过程。

New approaches will be developed for probing interfacial compositions of association colloids and vesicles over a wide range of surface charge densities and solution compositions. Product distributions from dediazoniation of an aggregate bound hydrophobic aryl diazonium salt will provide a "snapshot" view of interfacial nucleophile composition. This probe will be used to estimate, simultaneously, interfacial concentrations of water, and counterions, and also alcohol distributions and counterion selectivities. The effect of surface charge density on counterion binding and aggregate size and shape of micelles composed of amphoteric surfactants with phospholipid-like head groups will be determined by NMR, spectrophotometric, and potentiometric methods. %%% This grant from the Organic Dynamics Program supports the research of Professor Laurence S. Romsted at Rutgers University. Reactive species (aryl diazonium salts), bound to aggregated molecules (colloids and vesicles), will undergo reaction with solvent and other molecules at the aggregate-water interface to give a "snapshot" view of this interface. The effect of surface charge density on the aggregate and the shape of the aggregate will be determined by employing a variety of instrumental techniques. These studies will allow for a better understanding of an important biological process where the enzyme phospholipase A2 binds to phospholipid vesicles (aggregates).