Poly-(o-aminophenol)-Pd nanoparticle composite can be prepared by a single step, one pot chemical synthetic route at room temperature. similar to 2nm sized Pd-nanoparticles are encapsulated inside the needle-shaped polymer cage. IR and Raman spectra provide the information on the structure of the polymer. SEM and TEM images show the morphology of the polymer and the size of the metal particles respectively. (c) 2006 Springer Science + Business Media, Inc.