Extremely High Stability of Glutathionate‐Protected Au₂₅ Clusters Against Core Etching

Size matters: The core-etching reaction by free glutathione is studied for glutathionate (SG)-protected Aun(SG)m clusters with n=10–39 and m=10–24 (see picture). Only the Au25(SG)18 clusters remain unetched, whereas the Aun(SG)m clusters with n<25 and n>25 are transformed into a AuI:SG complex and stable Au25:SG, respectively. The selective synthesis of thiolate (SR)-protected Au25:SR on a large scale may be possible.