Acid catalyzed solutions of methyltriethoxysilane (MTES) mixed with tetraethoxysilane (TEOS) or titanbutilate (TiBut) were used to deposit silica and silica-titania coatings by dipping and spinning. Inorganic coatings free of cracks were obtained with a thickness up to 1.5 micrometers , after densification at 500 degree(s)C. The MTES derived coatings were used as matrices for metallic nanoparticles. Gold, silver and platinum nanoparticles were obtained in the coatings by thermal reduction. Gold particles were obtained at a temperature of 200 degree(s)C, while temperatures around 800 degree(s)C were necessary for silver and platinum. The effect of the composition of the matrix, the heat treatment temperature and the atmosphere on the formation of the particles was studied. The metallic particles were characterized by transmission electron microscopy, x-ray diffraction and UV-Vis absorption spectroscopy. The content of MTES and the heat treatment temperature were found to affect the dimension and the shape of the metal particles. The distribution in particle size may be tailored by choosing the heat treatment temperature and the amount of MTES.