ABSTRACT
Recently, however, more attention has been paid to the noble metal nanoparticles (NPs) and colloids due to their unique properties-even though gold colloids have been used for much longer. Artists have been working with colloidal suspensions to create colors for stained glass since the seventeenth century (Daniel, 2004). Then, in 1857, Faraday reported the successful formation of gold colloidal solution in one of his early published works on gold nanoparticles, describing its “beautiful ruby” color and the optical properties of the dried colloidal solutions on the film (Faraday, 1857). Other uses and synthesis methods may predate the era of peer-reviewed literature.
