Functionalization Of Glass Plate Surfaces By Pyrene Via A Long Flexible Spacer And Their Sensing Properties

The development of fluorescence sensors capable of recognizing metal ions, anions, and neutral molecules has attracted considerable interest in the recent past due to their high sensitivity and better selectivity. Fluorescence sensors can appear as molecular sensors or film sensors. Molecular sensors can be used only once, and using. of them will definitely contaminate sample solutions. Film sensors, however, can hopefully solve the problems mentioned above, and furthermore, film sensors are easy to be made into devices. Therefore, studies of fluorescence film sensors have attracted increasing attention during the last few years.Monomolecular assembly of small molecules onto substrate surface provides a convenient way to produce fluorescence film sensors. The properties of the functional surfaces depend upon a number of factors, including, at least, the nature of the small molecules, the properties of the substrate surface, the structure of the spacer, which links the small molecule and the substrate, and the density of the small molecules on the substrate surface. Clearly, a variety of functional films with ideal properties may be prepared by careful selection and combination of the small molecules, the substrates and the spacers.Based upon these considerations, a number of films sensors with pyrene (Py) or dansyl as fluorophores have been prepared and studied in our laboratory. These film sensors have been successfully used to detect the quality of water, nitrite in water, nitromethane in methanol or water, dicarboxylic acids and nitrobenzene in aqueous phase.The main goal of this dissertation is to interrogate the effects of the structure and properties of the spacer on the sensing properties of the functional films.First, we investigate the influence of the length of the spacer on the sensing properties of dicarboxylic acids film sensors. For selective sensing of dicarboxylic acids, imino units were intentionally introduced into the spacer. The reported sensors, containing 1,2-diaminoethane or 1,3-diaminopropane structure, suffered from slow response and low sensitivity to the analytes. The comparative results of these two film sensors revealed that the length of the spacer is crucial for the sensing behavior of the...