Thiolated ligands are known to form self-assembled monolayers on gold nanoparticles, and the self-organisation of these ligands provides a route towards nanoparticles with programmable and complex molecular structures. This body of work investigates the structures and chemical properties of ligand monolayers based on peptides and alkanethiol derivatives. We evaluate a series of published articles reporting the peculiar self-organisation of ligands into striated domains on the surface of nanoparticles, which was shown by scanning tunnelling microscopy (STM). Image analysis of the STM micrographs shows the stripe-like domains to be scanning artefacts, and our attempts to reproduce data on nanoparticle stability and cell entry give results conflicting with those published. Self-assembled monolayers made from peptides allow the use of peptide motifs to drive self-organisation. We investigate the effects of using an amyloidogenic sequence, CFGAILSS, in a monolayer. FTIR, 2DIR and solid state NMR reveal the presence of inter-peptide hydrogen bonding consistent with a parallel β-sheet structure, which is not seen in a monolayer made from the CALNN peptide. Fluorescently labelled peptide-capped gold nanoparticles were irradiated by a femtosecond laser pulse. The timings of the reaction dynamics of this ligand release were measured by splitting the laser beam and introducing a variable delay. These measurements show that this process is a hot electron mediated process. We suggest that such laser induced release measurements can provide some insights into the intermolecular interactions within the monolayer
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:569148 |
| Date | January 2011 |
| Creators | Shaw, Christopher Paul |
| Publisher | University of Liverpool |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
Page generated in 0.0018 seconds