Theoretical design of new class of optical materials based on small noble metal nanocluster-biomolecule hybrids and its potential for medical applications

This article was supported by the German Research Foundation (DFG) and the Open Access Publication Fund of Humboldt-Universität zu Berlin.The unique linear and non-linear optical (NLO) properties of small noble metal nanoclusters in hybrid systems formed with peptides will be overviewed. Focus is on two aspects based on theoretical concepts. First, enhancement of absorption of biomolecules by small silver clusters in non-scalable regime in which each atom counts will be illustrated on example of peptides involving aminoacids. Second, concept for design of new NLO-phores based on ligated noble metal nanoclusters in which ligands (peptides) have dual role stabilizing metal clusters and inducing non-linearity. Both complementary directions have attractive potential for medical application. The small silver clusters with their unique optical properties and simple linking to peptides should allow optical labelling of functional intracellular proteins opening perspective for development of new sensors. Understanding of leading factors giving rise to large non-linear properties of peptide ligated small silver nanoclusters allows to propose novel ligand-core NLO-phores for bioimaging as well as for other applications.Peer Reviewe