The etching reactivity of glutathionate (SG) protected Au n(SG)m clusters, where (n,m)=(10,10), (15,13), (18, 14), (22,16), (25,18), (29,20), (33, 22), and (39, 24) by free glutathione (GSH) under aerobic condition, was analyzed. It was observed that the colors of the solution of smaller Aun(SG)m cluster (core size n<25) faded after the addition of free GSH and became cloudy after three hours, while those for larger clusters (n≥25) did not exhibited appreciable color changes. The Au25(SG)18 and Au39(SG)25 showed the highest stability during storage in water for two weeks at ambient temperature. The high stability of Au25(SG)18 against core etching was contributed by chemical inertness arising from full protection by the SG ligands.
ASJC Scopus subject areas
- 化学 (全般)