3 years ago

Amino-Acid-Conjugated Gold Clusters: Interaction of Alanine and Tryptophan with Au8 and Au20

Amino-Acid-Conjugated Gold Clusters: Interaction of Alanine and Tryptophan with Au8 and Au20
Nabanita Saikia, Ravindra Pandey, Kevin Waters, Marwa H. Abdalmoneam
The stability and electronic properties of gold (Au) clusters interacting with the amino acids alanine (Ala) and tryptophan (Trp) in their canonical and zwitterionic configurations were investigated using first-principles density functional theory (DFT). We found that the geometrical structures of the Au clusters and the polarities of the amino acids determine the nature of the interactions in the gas and solvent phases. In the gas phase, the Au8 (D4h) and Au20 (Td) clusters prefer single-site interactions through the amine group for the canonical amino acids, whereas in the solvent phase, the carboxylic site is preferred for the zwitterionic amino acids. The limited screening of the intermolecular interactions introduced by the solvent medium for the canonical forms of Ala and Trp conjugated with the Aun complexes suggests that the bonding is primarily covalent in nature. The screening is significantly more pronounced for the zwitterionic complexes for which the electrostatic interactions dominate. The cluster sizes and configurations define the extent of the interactions and the overall stability of the complexes. The structures of the Aun clusters govern the charge distribution and electrostatic potential, directing the selectivity toward the preferential binding sites with the Ala and Trp amino acids.

Publisher URL: http://dx.doi.org/10.1021/acs.jpcc.7b09108

DOI: 10.1021/acs.jpcc.7b09108

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.