Fig. 2. (A) Schematic illustration of the reduction and decoration of GO nanosheets using BSA protein to develop a new platform for biosensing. (B) TEM images show AuNPs-decorated BSA-GO nanosheets with well-controlled AuNPs densities by increasing the concentration of BSA protein from 0.5 mg mL⁻¹ to 20 mg mL⁻¹ during BSA-GO hybrid formation. In (c) the density of AuNPs was further increased by the addition of 0.1 M NaCl to the BSA-GO assembly in (b). NaCl was not used for (a) and (b). [Reprinted with permission from ref. 63, J. Liu, S. Fu, B. Yuan, Y. Li and Z. Deng, Toward a Universal “Adhesive Nanosheet” for the Assembly of Multiple Nanoparticles Based on a Protein-Induced Reduction/Decoration of Graphene Oxide, J. Am. Chem. Soc., 2010, 132, 7279–7281. Copyright© American Chemical Society.].