The plasma chemical solvent-free method of doped and nanocomposite polyaniline-based (PANI-based) conductive coatings deposition was elaborated. Molecular structure, morphology, optical, electrical and sensing properties of PANI-based coating were investigated by Fourier transform infrared, UV-vis, impedance spectroscopy methods and transmittance electron microscopy. The synthesized PANI-based coatings containing silver nanoparticles have a partially doped structure with low variation in size of oxidized and reduced PANI units. The nanocomposite PANI-based coatings were deposited onto interdigital capacitor for ammonia gas sensing applications. The increasing of the sensing performance of the PANI-based coatings with silver nanoparticles was established in particular at the low frequency region of impedance spectra. The high sensitivity and linearity of this sensor response were examined at a direct and alternating voltage with ammonia concentrations up to 10 ppm. (C) 2015 Elsevier B.V. All rights reserved.