Size controlled gold nanoparticle formation by Avena sativa biomass: use of plants in nanobiotechnology

ARMENDARIZ; HERRERA; PERALTA; YACAMAN; TROIANI; SANTIAGO; GARDEA

JOURNAL OF NANOPARTICLE RESEARCH

SPRINGER

Lugar: Berlin; Año: 2004 p. 377 - 382

1388-0764

Oat (Avena sativa) biomass was studied as an alternative to recover Au(III) ions from aqueous solutionsand for its capacity to reduce Au(III) to Au(0) forming Au nanoparticles. To study the binding trend ofAu(III) to oat and the possible formation of Au nanoparticles, the biomass and a solution of Au(III) werereacted for a period of 1 h at pH values ranging from 2 to 6. The results demonstrated that Au(III) ionswere bound to oat biomass in a pH-dependent manner, with the highest adsorption (about 80%) at pH 3.HRTEM studies showed that oat biomass reacted with Au(III) ions formed Au nanoparticles of fcctetrahedral, decahedral, hexagonal, icosahedral multitwinned, irregular, and rod shape. To our knowledge,this is the second report about the production of nanorods as a product of the reaction of a Au(III) solutionwith a biological material. These studies also showed that the pH of the reaction influenced the nanoparticlesize. The smaller nanoparticles and the higher occurrence of these were observed at pH values of 3 and 4,whereas the larger nanoparticles were observed at pH 2.