Abstract
Nanoparticles are very interesting materials due to their properties which can be different than those of the bulk and they have
many applications in various domains, like electronic, catalytic or biomedical. Gold is one of the most studied materials and is
used in many applications that will have the human being as recipient, that’s why gold nanoparticles should be obtained as
environmentally friendly as possible. In this work, particles of around 50 nm were obtained in a so called “green” way by simply
adding a solution containing the gold precursor (HAuCl4) in a tannic acid solution. It was found that the amount of gold added in
the tannic acid is directly proportional with the size of the obtained nanoparticles.