Two self-assembled systems have been investigated for potential application to chemical biological (CB) defense; gold nanoparticles and functionalized dendritic polymers (dendrimers). The former system consists of nanometer-sized gold particles encapsulated by monomolecular layers of alkanethiol surfactant deposited as thin films on microelectrodes. These films have been shown to be sensitive as chemical vapor detectors. The latter system consist of antibody-dendrimer conjungates shown to improve the sensitivity of immunoassays for microorganisms as well as dendrimers derivatized with reactive groups which decontaminate 1-chloroethylsulfide. These same materials have been incorporated into a cream to provide topical skin protection against chemical agents.