Preparation of linoleic acid capped gold nanoparticles and their spectra

Gold nanoparticles have been prepared through the chemical reduction of tetrachloroaurate ions by ethanol with linoleic acid as a protecting layer to the nanoparticles. X-Ray diffraction study and transmission electron microscopy (TEM) reveal that the particles are mostly spherical in shape with an average size of nearly 10 nm. The UV/vis absorption spectra show absorption maximum at 510 nm, which is due to surface plasmon resonance (SPR). Photoluminescence spectra of gold nanoparticles have also been analysed, which show an emission peak at 770 nm when illuminated at 550 nm. The most important fact is that the produced nanoparticles remain stable for more than 1 week.