A new concept in bactericidal agents is described: the entrapment of an organic biocidal agent within a bactericidal metal, which leads to synergism between the two components. Specifically this concept is demonstrated for the entrapment of chlorhexidine digluconate (CHD) within an aggregated silver matrix, a metal known for its own biocidal qualities, forming the CHD@silver composite. The bactericidal efficacy against E. coli is evaluated and compared with the separate components. While the bactericidal efficacy of the individual ingredients (CHD and metallic silver) is very low, CHD@silver exhibits a markedly enhanced efficacy. This enhanced bactericidal effect is partially attributed to the simultaneous release and presence of the active biocidal ingredients CHD and Ag+ in the solution. Detailed composite characterization is provided.