ABSTRACT
Fluorescent metal nanoclusters (NCs) gained a bourgeoning interest in the field of nanomaterials due to the special properties of ultra-small size, low toxicity, excellent photostability and bio-compatibility. With the size approaching to the Fermi wavelength of electrons, metal NCs possess molecule-like properties and excellent fluorescence emission. As the photophysical properties of such NCs materials depend strongly on size, focus is laid on development of synthetic routes that allows precise tuning of the cluster cores with high monodispersity and purity. Various small molecules, proteins, polyelectrolytes etc. are used for the direct one-pot synthesis of noble metal fluorescent nanoclusters and applied for the sensing of metal ions including other analytes. The novel optical properties render the fluorescent noble-metal nanoclusters as ideal fluorophores for multicolor and multiplexing applications in biomedical engineering and molecular biotechnology. This chapter provides an overview of the properties, synthesis and their applications for the detection of metal ions.
