Extended Data Fig. 3: Identification of the species of gold-thiolate in the mixtures of HAuCl4 and RSH by MALDI-TOF analysis.
From: Genetically encoded tags for direct synthesis of EM-visible gold nanoparticles in cells
a, Two types of gold thiolate compounds identified in the 1:1 Au(III)/(D-P) mixture at RS−/Au(III) < 2:1 condition: Au(I)n(D-P)n+1, (n = 2,3,4) in zigzag chain forms (labeled as black), and the Na(1-2)Au2(D-P)4Cl2O compounds (labeled as red). b, Only the soluble Na(1-2)Au2(D-P)4Cl2O formed in the Au/D-P mixture at RS−/Au(III) > 2:1 condition. c, In the mixture of 0.5 mM HAuCl4 + 60 mM 2-ME (RS−/Au(III) < 2:1 condition), the major Au(I) thiolate species were zigzag chain-like 1:1 Au(I)/(2-ME) compounds (in black), mixed with a little amount of Na2Au(III)(2-ME)4 (in green) and 1:2 Au(I)/(2-ME) compounds (in red). d, In the mixture of 0.5 mM HAuCl4 + 160 mM 2-ME (RS−/Au(III) > 2:1 condition), the amount of zigzag chain-like 1:1 Au(I)/(2-ME) compounds (in back) were largely reduced, and Na(0-2)Au(III)(2-ME)4 (in green) became the major species, and also found some 1:2 Au(I)/(2-ME) compounds (in red).e, Additional 20 mM D-P to the 0.5 mM HAuCl4 + 60 mM 2-ME mixture, only the Au(III) compounds (in green) and a little amount of NaAu2(D-P)4Cl2O (red) found in the mixture. f, In the 0.1 mM HAuCl4 and 150 mM 2-ME mixture, only three 1:2 Au(I)/(2-ME) compounds (red) formed at such RS−/Au(III) > 2:1 condition. Representative images for (a-f) were selected from n = 2 independent experiments with similar results.
