Abstract
A thin-layer film comprising poly(methyl methacrylate) with an incorporated pyrazolo[3,4-b]quinoline derivative was prepared. The dye was anchored onto the polymer film to form a molecular assembly at the surface. Fluorescence quenching of this thin-layer sensory system was observed when the film was incubated in the presence of the nucleotide guanosine-3′,5′-cyclic monophosphate. Steady-state and time-resolved fluorescence techniques were used to study the fluorescence quenching of this sensory system in the presence of nucleotides. The results suggest that quenching of a pyrazoloquinoline fluorosensor by nucleotide anions cannot be described simply by a collision mechanism employing the Stern-Volmer equation, but there is a possibility of the formation of a more stable association. This type of sensing polymer layer plays a role in biotechnology because it can be immobilized at the end of a fibre optic and used for measuring nucleotide concentrations within a biological system.