Fluorescence properties of immobilized pyrene on quartz surface

A novel nitrite sensing film has been prepared by chemical immobilization of pyrene (Py) onto an aminiated quartz plate surface. Fluorescence excitation and emission measurements and fluorescence quenching studies demonstrated that the immobilized fluorophore, Py, exists mainly in isolated state, rather than aggregated state. The profile and intensity of the emission of the plate are hardly affected by the presence of common chemicals including fluorescence quenchers like TlNO3, Cu(NO3)2, and CH3NO2. Changes in pH values from 2 to 8 has little effect upon the emission. Introduction of a small amount of nitrite, however, quenches the fluorescence emission significantly. The quenching is very pH dependent and is totally reversible. This makes it a potential sensing materials for nitrite. The analytical applications of the plate have been conducted in our laboratory.