ANYL 403 |
| One- and two-step strategies were developed to deposit fluorescent coatings on different solid supports, such as quartz, glass and silica nanoparticles. Electron deficient 2,7-diazapyrenium derivatives were synthesized and used as receptors because their interaction with electron rich substrates can be monitored by fluorescence measurements. The hydroxylated surfaces were chemically modified by silanization or using a sol-gel process. After immobilization of the receptor, the modified supports were characterized by appropriate analytical methods including absorption and emission spectroscopies, fluorescence microscopy, among others. The application of the fluorescent coatings for the detection of dopamine was studied. The supramolecular assembly formed by the receptor and the analyte at the solid/water interface produces a decrease in the fluorescence intensity, which is proportional to the analyte concentration. We found that the fluorescent silica nanoparticles prepared in one step, are the most sensitive coatings for dopamine detection with an association constant around 2600 M1. |
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General Papers
8:30 AM-11:35 AM, Wednesday, 31 August 2005 Washington DC Convention Center -- 153, Oral
Sci-Mix
Division of Analytical Chemistry |