In this work a novel antibacterial surface composed of an organic-inorganic hybrid matrix of tetraorthosilicate and a polyelectrolyte is presented. A precursor solution of tetraethoxysilane (TEOS) and poly(acrylic acid sodium salt) (PAA) was prepared and subsequently thin films were fabricated by the dip-coating technique using glass slides as substrates. This hybrid matrix coating is further loaded with silver nanoparticles using an in situ synthesis route. The morphology and composition of the coatings have been studied using UV-VIS spectroscopy and atomic force microscopy (AFM). Energy dispersive X-ray (EDX) was also used to confirm the presence of the resulting silver nanoparticles within the thin films. Finally the coatings have been tested in bacterial cultures of genus Lactobacillus plantarum to observe their antibacterial properties. It has been experimentally demonstrated that these silver loaded organic-inorganic hybrid films have a very good antimicrobial behavior against this type of bacteria.