alpha-Alkyl cysteine-coated gold nanoparticles: effect of C alpha-tetrasubstitution on colloidal stability

作者:Osante Inaki; Polo Ester; Revilla Lopez Guillermo; de la Fuente Jesus M; Aleman Carlos; Cativiela Carlos; Diaz Diaz David*
来源:Journal of Nanoparticle Research, 2014, 16(2): 2224.
DOI:10.1007/s11051-013-2224-y

摘要

In this work, we report the synthesis of new alpha-methyl L-cysteine-coated gold nanoparticles (average core diameter ca. 3 nm) and the remarkable enhancement of their aqueous stability against aggregation in comparison with the nanoparticles capped with unmodified L-cysteine under the same experimental conditions. Atomistic molecular dynamics simulations of model gold surfaces capped with L-cysteine or alpha-methyl L-cysteine revealed important differences in both the organization of the amino acids with respect to the surface and their spontaneous assembly with neighboring molecules. These differences, which are originated by the introduction of the alpha-methyl group in the amino acid, could be associated with the observed increase in stability and dispersibility of the composites in aqueous solutions at different pH values and ionic concentrations.

  • 出版日期2014-1-10