Fig. 41. Schematic representation of nGO-based biosensor array. (a) GO–protein binding and interactions showing GO as a quencher for fluorophores. The fluorescence is restored by the displacement of quenched fluorophores due to the interactions between GO and the analyte proteins. Statistical analysis of the displaced fluorophores using LDA to examine differences in the GO–protein interactions between conventional GO and nGO flakes (20 nm diameter). (b) LDA patterns showed enhanced fluorescent restoration from a three sensor array of nGO flakes compared to that obtained with conventional GO. The nGO showed a high fluorescence response due to increased protein interactions compared with those observed for conventional GO flakes. (c) Chemical structures of the five fluorophores, including acridine orange, pyronine Y (PY), rhodamine B, rhodamine 6G (R6G) and His-tagged emerald green fluorescent protein (eGFP), used for the fluorescent sensor array. Reprinted with permission from ref. 753, S. S. Chou, M. De, J. Luo, V. M. Rotello, J. Huang, V. P. Dravid, Nanoscale Graphene Oxide (nGO) as Artificial Receptors: Implications for Biomolecular Interactions and Sensing, J. Am. Chem. Soc., 2012, 134, 16725–16733. Copyright© 2018 American Chemical Society.