Gold nanoparticles are not, normally, fluorescent. However, when they are very small, typically below 2nm, strange things happen… Nicolas Schaeffer paper, entitled, “Fluorescent or not? Size-dependent fluorescence switching for polymer-stabilized gold clusters in the 1.1–1.7 nm size range” has now been published in Chem. Comm.
Meanwhile, Nicolas is busy presenting his data at the International symposium on monolayer-protected clusters, ISMPC08, in Finland. He is in good company.