This study is aimed at the development of nanosilver embedded polyacrylamide (PAAm) bioactive nanogels and antimicrobial behavior of these functional nanogels. Nanogels were synthesized by polymerization of the monomer/silver nitrate as water phase in nanoemulsion using gamma irradiation process where radiation helps in the polymerization, nanogel crosslinking and the reduction of silver nitrate to nanosilver. Homogeneously dispersed nanosilver particles embedded within PAAm nanogel matrix having size in the range of 10-50 nm were achieved depending on the reaction conditions. Minimum inhibitory concentration and bacteriostatic efficacy of nanogels were investigated against bacterial strains of Escherichia coli and Staphylococcus aureus. The bioactive nanogels showed very effective antimicrobial behavior and showed mortality against both bacterial strains at very low concentration. The bactericidal action of functional silver nanoparticles against Escherichia coli was investigated by TEM analysis. It was observed that after treatment with bioactive nanogel, the cell wall of Escherichia coli was completely destroyed and punctured. Here, we propose that the bioactive nanogel by virtue of its hydrophilic and polar functionality is very much suitable for linking to different biomaterials for developing antimicrobial surfaces especially in surgical devices and synthetic implants.