Gold nanoparticles are one of the most widely used nanomaterials for academic research, point-of-care medical devices and industrial products due to their stability, optical properties and multiple surface functionalities. The optical and electronic properties of gold nanoparticles are tunable by changing the size, shape, surface chemistry, or aggregation state. Chemical reduction is the most popular method to synthesize well defined metallic nanoparticles. Although this method offers significant advantages of simple equipment and convenient operation, it involves the use of toxic, hazardous chemicals, which may pose potential environmental and biological risks.

The nanoparticles offered by TORSKAL are produced by green chemistry (by bio-reduction of metal salts HAuCl4), with crude and / or purified extracts from plants. These extracts have the double action of reducing the metal and stabilizing the nanoparticle formed. The size and shape of the nanoparticles formed can be modulated by various factors during the synthesis. The synthesis of nanoparticles by using the bio-reducing potential of plant extracts has been demonstrated in various studies in recent years. Based on this observation, TORSKAL developed a green chemistry approach to synthesize nanoparticles using endemic plants originated from Reunion Island. Plants extracts have the double action of reducing the metal and stabilizing the formed nanoparticles.

The obtained nanoparticles are fully characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta-potential, XRD, UV-Vis, FTIR and Raman spectroscopy to understand their physicochemical and biological properties.