title: Silver cluster-biomolecule hybrids: from basics towards sensors.
abstract: We focus on the functional role of small silver clusters in model hybrid systems involving peptides in the context of a new generation of nanostructured materials for biosensing. The optical properties of hybrids in the gas phase and at support will be addressed with the aim to bridge fundamental and application aspects. We show that extension and enhancement of absorption of peptides can be achieved by small silver clusters due to the interaction of intense intracluster excitations with the π-π* excitations of chromophoric aminoacids. Moreover, we demonstrate that the binding of a peptide to a supported silver cluster can be detected by the optical fingerprint. This illustrates that supported silver clusters can serve as building blocks for biosensing materials. Moreover, the clusters can be used simultaneously to immobilize biomolecules and to increase the sensitivity of detection, thus replacing the standard use of organic dyes and providing label-free detection. Complementary to that, we show that protected silver clusters containing a cluster core and a shell liganded by thiolates exhibit absorption properties with intense transitions in the visible regime which are also suitable for biosensing applications.
authors.affiliation: Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany. vbk@chemie.hu-berlin.de
authors.forename: Vlasta
authors.initials: V
authors.lastname: Bonačić-Koutecký
authors.forename: Alexander
authors.initials: A
authors.lastname: Kulesza
authors.forename: Lars
authors.initials: L
authors.lastname: Gell
authors.forename: Roland
authors.initials: R
authors.lastname: Mitrić
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Antoine
authors.forename: Franck
authors.initials: F
authors.lastname: Bertorelle
authors.forename: Ramzi
authors.initials: R
authors.lastname: Hamouda
authors.forename: Driss
authors.initials: D
authors.lastname: Rayane
authors.forename: Michel
authors.initials: M
authors.lastname: Broyer
authors.forename: Thibault
authors.initials: T
authors.lastname: Tabarin
authors.forename: Philippe
authors.initials: P
authors.lastname: Dugourd
mesh_terms: D015374:Biosensing Techniques; D005740:Gases; D008954:Models, Biological; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D044367:Phase Transition; D012834:Silver / Q000737:chemistry*
chemical_list: D005740:Gases; D010455:Peptides; D012834:Silver