PH-Dependent Synthesis of Anisotropic Gold Nanostructures by Bioinspired Cysteine-Containing Peptides.

ABSTRACT: In the present study, alkaline peptides AAAXCX (X = lysine or arginine residues) were designed based on the conserved motif of the enzyme thioredoxin and used for the synthesis of gold nanoparticles (GNPs) in the pH range of 2-11. These peptides were compared with free cysteine, the counterpart acidic peptides AAAECE and γ-ECG (glutathione), and the neutral peptide AAAACA. The objective was to investigate the effect of the amino acids neighboring a cysteine residue on the pH-dependent synthesis of gold nanocrystals. Kohn-Sham density functional theory (KS-DFT) calculations indicated an increase in the reducing capacity of AAAKCK favored by the successive deprotonation of their ionizable groups at increasing pH values. Experimentally, it was observed that gold speciation and the peptide str

SUBMITTER: Tofanello A 

PROVIDER: S-EPMC6640750 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature