As researchers or salesman in chemical or biological field, we know TRIS (Tris(hydroxymethyl)aminomethane) very well. It is widely used as buffer in biochemical and molecular biological experiments, effective buffering range of TRIS buffer is pH 7.0~9.2.

In addition, TRIS (CAS 77-86-1) is also an intermediate of surfactants, vulcanization accelerators and some drugs.

But in the following paragraphs, we will introduce the function of TRIS as a good reducing agent to prepare gold nanoparticles. Because of the three equivalent hydroxyl groups, under the alkaline condition of sodium hydroxide, the chloroauric acid solution can be reduced to prepare stable gold nanoparticles without toxicity and pollution.

At present, the classic methods for the synthesis of gold nanoparticles are sodium citrate reduction method, phase transfer method and seed growth method. These methods are most likely to carry out surface biomolecule modification on gold nanoparticles, but the processes of preparation and modification have some toxicity. In order to reduce the toxicity of gold nanoparticles to biological organisms in the experiment, so that it can be better used in the field of biomedical applications, researchers are committed to developing new green reduction method in recent years.

When TRIS is used as a reducing agent to reduce the chloroauric acid solution under alkaline conditions, it can get relatively stable gold nanoparticles without adding other stabilizers. By adjusting the experimental conditions, different sizes of nano-gold particles can be prepared.

Compared with other green synthesis method, the experimental conditions are more moderate and easy to operate. And it provides a new research ideas and theoretical basis for the synthesis of green, non-polluting, low toxicity, low cost and high biocompatibility of gold nanoparticles.