Spherical monodisperse nanoparticles composed of gold or silver cores were modified with lipids as part of an ongoing project to utilize functionalized nanoparticles as drug delivery vehicles. A reduction reaction with sodium tri-citrate was used to synthesize nanoparticles that were characterized physically through a NanoSight LM10 HS particle sizer as well as optically with a Shimadzu UV-vis spectrophotometer. The particles were then characterized again after purification of excess ligands through centrifugation. Poly(allylamine hydrochloride) was added to flip the surface charge of the particles from negative to positive as well as to serve as a stabilizing agent. After purification, the particles were coated with lipids and spun to purify them. Characterization data suggest that the particles are successfully coated with both poly(allylamine hydrochloride) and lipids and that monodispersity was maintained, as evidenced by the measured changes in size and optical properties
