An organically modified silicate (ormosil) as a matrix for the fabrication of dissolved oxygen-sensing film was produced. The process included taking tetramethoxysilane (TMOS) and dimethyldimethoxysilane (DiMe-DMOS) as precursor and running a reaction at 60 degreesC in an open vial, which accelerates hydrolysis and condensation and results in the formation of emulsion. The film doped with tris-(4,7-diphenyl-1,10-phenanthroline) ruthenium(H) ([Ru(dpp)(3)](2+)) as an oxygen indicator exhibited a good linear relationship, fast response time, long-term stability and enhanced sensitivity to dissolved oxygen after optimizing the sol-gel processing parameters. The properties and the oxygen-sensing behavior of the film were investigated. The results presented here emphasized the significance of ormosil as a matrix for dissolved oxygen-sensing. (C) 2002 Elsevier Science B.V. All rights reserved.