The problem of creation of optical chemical and biological sensors for express analysis of the environment, products of vital activity, and industrial wastes on the concentration of harmful substances has become an object of priority investigations in the nanotechnology sphere abroad and in Russia. In particular, in 1 the method of obtaining structured optical chemosensory films on the basis of nanosize particles of silica (5-8 nm in size) modified by organic dye is stated. This material is a mesoporous silica with the area of the inner pore surface significantly exceeding 100 m~2/g with a luminescent dye connected with the silica particles directly by hydrogen bonds or by bonds containing partly long chains of strongly basic cations of quaternary ammonium. Sensor features of the films were proved by an optical response expressed in quenching of fluorescein luminescence as a result of ammonia joining. The very small sizes of the material pores (about 1-2 nm) permit quick penetration of the liquid or gas analyzed into the film. So, the film surface mainly takes part in the decrease of photoluminescence (PL) of dye intensity during the analysis. This results in a decrease in the optical response intensity and is a defect of such a type of sensory material.
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