A simple and inexpensive, single step synthesis of silver nanoparticles was achieved using poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA) both as a reducing and stabilizing agent. The synthetic process was carried out in aqueous solution, making the method versatile and ecofriendly. The synthesized polymer stabilized nanoparticles were stable in water at room temperature without particle aggregation for at least 1 month. The synthesized silver nanoparticles were characterized by UV-visible absorption spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), and Fourier transform IR spectroscopy (FTIR). Results showed that Ag-core nanoparticles were coated with PVM/MA shell with thickness of about 5 to 8 nm. The antimicrobial activities of the copolymer (PVM/MA) stabilized silver nanoparticles on various microorganisms were also studied. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 21892196, 2011