a high resolution sem optical absorption measurements also show the 520 nm surface plasmon band of the gold nanoparticles when taken in the reflectance mode tem measurements further indicate the capping of gold nanoclusters in the network of the polymer membrane this example illustrates the process for the preparation of large area freestanding polymer membranes incorporated in situ with gold nanoparticles a 100 ml aqueous solution of 10 u2212 3 m chloroauric acid was added with 10 u2212 3 m 2 bis 4 aminophenoxy diethylether dissolved in chloroform under static ambient experimental conditions this mixture is left static for 3 5 hours after 5 hours a freestanding thicker polymer membrane is formed at the liquid liquid interface between the organic and aqueous phases the dark purple color of the membrane itself indicates that the gold nanoparticles are incorporated into them the as formed membrane is transformed to si 111 and glass substrates for further characterization an average particle size of a few micron was observed for the incorporated gold nanoclusters in the polymer membrane using a high resolution sem optical absorption measurements also show the 520 nm surface plasmon band of the gold nanoparticles when taken in the reflectance mode tem measurements further indicate the capping.