Fluorescent, molecularly imprinted thin-layer films based on a common polymer

Fluorescent, molecularly imprinted polymer thin films, with cyclic guanosine 3',5'-monophosphate (cGMP) as a template and 1,2-diphenyl-6-vinyl-1H-pyrazole-[3,4-b]-quinoline as a fluorescent receptor, were prepared according to a method based on commercially available poly (methyl methacrylate). This method of preparation predicts photoinduced crosslinking in the mixture of polymer chains and involved components. The advantages of this method are the relative simplicity of its preparation and the fact that a common polymer can be used. The spin-coated thin-layer films of imprinted and nonimprinted polymers were studied with the use of fluorescence microscopy with a scanning range of 80 x 80 pm. A strong fluorescence quenching effect was observed when a cGMP-imprinted film was incubated in aqueous solutions of cGMP, but a comparatively small effect was observed for a nonimprinted polymer and when an imprinted film was incubated with cyclic adenosine 3',5'monophosphate (cAMP). The separation factor by the imprinted polymer was determined to be 2.55 for cGMP against cAMP. The obtained polymeric sensor appeared to be stable during subsequent measurements after rewashing and readsorption. The homogeneity of the surface of the polymer film, dependent on the method of film preparation, was also studied. (C) 2007 Wiley Periodicals, Inc.