Figure 1.

Synthesis and UV-vis absorption spectra of AuNCs. (A) Schematic representation of AuNC synthesis. AuNCs surfaces were modified with glutathione (SG) and PEG. Following the controlled reduction of gold with L-glutathione, AuNCs were PEGylated using the peptide coupling method described in the Methods section. (B) Absorbance spectra of Au₁₅ and Au₂₅ nanoclusters. Absorbance spectra for the different AuNCs indicated were obtained at a final concentration of 100 µM in water.