Grafting of cobalt porphyrins in sol–gel matrices: application to the detection of amines

Grafting in a sol–gel matrix is of interest since it provides materials which are transparent with a good optical quality and which are compatible with the use of optical fibers in spectroscopic detection. Grafting of cobalt(II)porphyrins in a sol–gel matrix was realized using a porphyrin substituted by a triethoxysilyl group and pure tetramethoxysilane as the precursor. Comparison was achieved between grafted and non-grafted porphyrins. Preliminary results on pyridine sensing show that the diffusion of pyridine occurs with a lower rate than in organic matrices.