Metallic non-luminescent nanoparticles (NPs) and non-metallic luminescent nanoclusters (NCs) of the same element are two exciting groups of nanomaterials exhibiting entirely different optical, physical and chemical properties.  We have developed  a synthetic rationale to grow an array of silver/gold NPs and NCs using ligands made of polyethylene glycol (PEG) segment appended with thioctic acid (TA) and terminated by inert (-OCH3) or reactive (-COOH/-NH2) groups.  The particle size can be controlled by varying the metal-to-ligand molar ratios and tuning the solution conditions.  We also found that this route allows polydisperse AgNPs to be size-focussed into monodisperse and fluorescent AgNCs.  The NCs are highly luminescent and they emit in the far red to near infrared (NIR) region of the optical spectrum; they also exhibit great colloidal stability.  Introduction of PEG segments in the ligand promotes water solubility while allowing subsequent functionalization and potential coupling to target biomolecules.

Synthesis and in situ functionalization of silver/gold nanoparticles and luminescent nanoclusters by direct reduction and size focusing

244th National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.