Optical Ion Sensors Based on LB Films

为了设计一种基于模式识别的多通道传感系统，研究了十八烷基罗丹明B双膜对各种无机阴离子的荧光响应。采用十四种阳离子两亲体，双链两亲体和带有刚性芳香段的单链两亲体作为传感双层膜。双层膜的荧光响应不仅强烈依赖于无机阴离子，而且强烈依赖于形成双层膜的两亲化合物的化学结构。液态双膜比凝胶态双膜更敏感。碘离子对大多数双层膜起荧光猝灭剂的作用。碳酸盐离子特异性地增强了单链紫堇两亲体双层膜的荧光强度。基于双层膜的荧光响应研究了阳离子两亲体与反电荷聚电解质、聚乙烯磺酸盐、聚乙烯基硫酸盐和羧甲基纤维素络合的Langmuir-Blodgett膜的荧光响应。反电荷聚合物的化学结构强烈影响荧光响应，即使相同的两亲性被用作单层形成化合物。在多通道离子传感器的分子设计中，分子膜荧光的多样性是必不可少的。

In order to design a multi-channel sensing system based on pattern recognition, fluorescence response of bilayr membranes having octadecylrhodamine B to various inorganic anions were investigated. Fourteen cationic amphiphiles, double chain amphiphiles and single chain amphiphiles with a rigid aromatic segment, were used as the sensing bilayr membranes. Fluorescence response of bilayr membranes was strongly depend not only on inorganic anions but also on the chemical structure of the bilayr forming amphiphile. Fluid bilayr membranes were more sensitive than those of gel state. Iodide ion act as a fluorescence quencher of the most bilayr membranes. Carbonate ions specifically enhanced fluorescence intensity of the bilayr membrane of a single chain viologen amphiphile. Based on the results of the bilayr membranes fluorescence responses of Langmuir-Blodgett films of the cationic amphiphiles complexed with counter charged polyelectrolites, Poly(stirenesulfonate), poly(vinylsulfate), and carboxymethyl-cellulose, were investigated. The chemical structure of the counter charged polymer strongly affected the fluorescence response even if the same amphiphile was used as a monolayr forming compound. A large variety of the fluorescence of the molecular films is essential to the molecular design of the multi-channel ion sensors.