Size Exclusion Chromatography for Semipreparative Scale Separation of Au₃₈(SR)₂₄ and Au₄₀(SR)₂₄ and Larger Clusters
Résumé
Size exclusion chromatography (SEC) on a semipreparative scale (10 mg and more) was used to size-select ultrasmall gold nanoclusters (<2 nm) from polydisperse mixtures. In particular, the ubiquitous byproducts of the etching process toward Au₃₈(SR)₂₄ (SR, thiolate) clusters were separated and gained in high monodispersity (based on mass spectrometry). The isolated fractions were characterized by UV–vis spectroscopy, MALDI mass spectrometry, HPLC, and electron microscopy. Most notably, the separation of Au₃₈(SR)₂₄ and Au₄₀(SR)₂₄ clusters is demonstrated.