Reaction of chloroauric acid with histidine in microdroplets yields a catalytic Au-(His)₂ complex.

ABSTRACT: An aqueous solution containing histidine (His, 100 μM) and chloroauric acid (HAuCl₄, 10 μM) is electrosprayed (-4.5 kV) from a capillary (50 μm in diameter) with N₂ nebulizing gas (120 psi). The resulting microdroplets entered a mass spectrometer with a 2 cm flight path. The mass spectrum recorded in negative ion mode showed several peaks including the Au₅ nanocluster with the major one being [Au + 2His-2H]^-, which is a catalytically active species. The reaction time was less 1 ms, and the yield of [Au + 2His-2H]^- was 76%. In contrast, the bulk reaction for the same concentration run at room temperature for 2 h did not produce this species but instead formed Au₁₀ nanocluster. When a solution of water and acetonitrile (1 : 1)

SUBMITTER: Luo K 

PROVIDER: S-EPMC8157187 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature