Development of analytical methods based on specificity of interfaces and their structural and kinetic stulies

在分析反应场方面，研究了硅材料的固液界面、液液界面、介孔通道、金和半导体纳米颗粒，利用氢键人工受体获得对分子和离子的高选择性和/或特异性识别。用具有分子或离子识别位点的硫代化合物修饰的金纳米颗粒。在水中加入目标分子或离子后，经过化学修饰的金颗粒呈现出由红色到蓝色的戏剧性变化。利用硫代羧基化合物修饰纳米级半导体粒子，利用光致电子转移机制成功制备出感应铅离子。利用液-液界面作为识别场，成功实现了对极亲水性阴离子的高选择性感应。采用动态界面张力法研究了硫脲基双功能受体与碱金属离子和阴离子在1,2-二氯乙烷-水界面上的离子对络合行为。当在水相中加入碱金属盐时，界面张力的降低是由有机相中受体的界面吸附引起的。受体的吸附常数取决于碱金属盐。结果表明，尽管阴离子水合作用有明显的干扰，但受体与阴离子之间的氢键在液-液界面上是有效形成的。受体在液-液界面上的一个更重要的特性是磷酸二氢比氯化物更优先结合。这种选择性仅在基于离子载体的化学传感器中观察到，如离子选择电极，其中选择性主要由分析物阴离子水化自由能的顺序决定。液滴极谱法还研究了阴离子从水相到水相的转移。形成氢键的双硫脲能够有效地促进各种亲水性阴离子在硝基苯-水界面上的转移，这表明该受体可能用于安培传感模式的多分析物检测。此外，研究了离子载体促进氯离子在硝基苯-水界面上的转移，观察到一个明确的波，表明离子载体通过形成氢键促进了氯离子在界面上的转移。离子转移极谱分析表明，氯离子的转移是由2与氯离子之间1:1的络合作用辅助的，转移过程是可逆的，并受离子载体从本体有机相向界面扩散的控制。尽管单硫脲的结合模式简单，基于两点相互作用，但与四个氢键参与氯离子结合的离子载体相比，单硫脲表现出较强的氯离子转移能力。动力学研究也进行了激光光谱。少

As to analytical reaction fields, solid-liquid interface, liquid-liquid interface, meso-porous channels of silcate material, gold and semiconductor nano particles are investigated to obtain highly selective and/or specific recognition of molecules and ions using hydrogen bonding artificail receptors. Gold nano-particles modified with thiolated compounds which have molecule or ion recognition sites. The chemically modified gold particles show dramatic color change from red to blue by addition of target molecules or ions in water. Nano-sized semiconductor particles were also modified by thiolated carboxylic compounds, and sensing lead ions was succesfully attained based on photo-induced electron transfer mechanism. Highly selective sensing of very hydrophilic anions was succeeded using liquid-liquid interfaces as recognition fields. Ion-pair complexation behaviors of a thiourea-based bifunctional receptor with alkali metal ions and anions are examined at the 1,2-dichloroethane-water inte … More rface by dynamic interfacial tensiometry. A decrease in the interfacial tension, caused by the interfacial adsorption of the receptor in the organic phase, is promoted when alkali metal salts are added in the aqueous phase. The adsorption constants of the receptor depend on alkali metal salts. The results indicate that hydrogen bonding formation between the receptor and anions is actually effective at the liquid-liquid interface despite the significant interference from anion hydration. A more important property of the receptor at the liquid-liquid interface is the preferential binding of dihydrogen phosephate over chloride. This kind of selectivity has merely observed in ionophore-based chemical sensors such as ion-selective electrodes, where the selectivity is governed predominantly by the order of the free energy of hydration of the analyte anions. Anion transfer from aqueous phase to water phase was also investigated by liquid droplet polarography, A hydrogen bond-forming bis-thiourea was able to effectively facilitate the transfer of various hydrophilic anions across the nitrobenzene-water interface, suggesting possible use of the receptor for multianalyte detection with an amperometric sensing mode. In addition, chloride transfer across the nitrobenzene-water interface facilitated by the ionophore was studied, and a well-defined wave could be observed, indicating that the chloride transfer across the interface was facilitated by the ionophore via formation of hydrogen bonds. The analysis of ion transfer polarograms showed that the chloride transfer was assisted by 1 : 1 complexation between 2 and chloride, and the transfer process was reversible and controlled by diffusion of the ionophore from the bulk organic phase to the interface. Despite its simple binding mode based on two point interactions, mono-thiourea showed a strong ability to facilitate chloride transfer compared with a ionophore in which four hydrogen bonds were involved in the chloride binding. Dyanamical studies were also carried out by laser spectroscopies. Less