ABSTRACT In this study, the Layer-by-Layer ubL) deposition technique was used to prepare composite thin films of silver nanoparticles and polyaniline. The multilayer composite thin films were constructed by alternate deposition of anionic and cationic polyelectrolytes.Anionic polyelectrolyte was prepared by chemical reduction of silver ion using water soluble polyaniline as the stabilizing agent to form anionic silver solution. The water soluble polyaniline was prepared by interfacial composite nanoparticles/polyaniline sulfonic acid co maleic acid). (CoPSS). polymerization of aniline monomer in presence of poly(styrene stabilized w anionic water soluble polyaniline were then débated in thin film nanoparticles Silver(PDADMAC) and characterized for their optical chloride) poly(diallyldimethylammonium with cation ic e spectroscopy. The surface ties. The optical properties of thin films were measured by uv e microscopy(AFM). As these films are to be used as sensor was measured by a detection, the changes in optical properties of the films were evaluated for various for the ammonia concentration. A strong color shift from orange-re to yellow was visible when exposed t ammonia composite thin films displayed fast color change and nanoparticles/polyaniline ammonia. These silver could be used for ammonia sensing in industrial section o 2014 Elsevier B.V. All rights reserved