We designed and prepared novel hybrid films of nanoparticles consisting of gelatin-g-poly(methyl methacrylate) (PMMA)/silver (Ag) polymers with ordered nanoporous, higher antibacterial activities. First, the gelatin-grafted PMMA microspheres were fabricated with the in situ copolymerization of gelatin and alkenes under radical initiation, which acted as a stabilizer and regulator for Ag nanoparticle growth. Then, silver nitrate was entrapped in a copolymerization system at 40 degrees C for 30 min. Finally, the gelatin-g-PMMA/Ag polymer hybrid films were prepared by the reduction of Ag+ with hydrazine, followed by emulsion solidification. The antibacterial activities of the gelatin-g-PMMA/Ag polymer hybrid films against Escherichia coli and Staphylococcus aureus were found with the disc diffusion method and colony count assays to be clear and lasting. In this study, our work not only presented a good example of a nanoporous antibacterial film material but also provided a facile method for making use of gelatin and metal/inorganic self-assemble properties in graft copolymerization to prepare functional polymer hybrids, such as antibacterial, antithrombogenic, and dot-quantum effect materials. (c) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 2617-2625, 2010