Fig. 15. Different graphene nanocomposite-based electrode materials for the detection of H2O2 in living cells. (A) Schematic representation of the in vitro detection of H2O2 using the rGO-PMS@AuNP/GCE. (B) Amperometric response of the rGO-PMS@AuNPs/GC electrode (i) with and (ii) without of HeLa cells after sequential addition of PMA and catalase to 0.1 M PBS at −0.75 V. (C) Cellular assay comparison of H2O2 detection for HEK 293, HeLa, and HepG2 cells. [Reprinted with permission from ref. 330, S. K. Maji, S. Sreejith, A. K. Mandal, X. Ma and Y. Zhao, Immobilizing Gold Nanoparticles in Mesoporous Silica Covered Reduced Graphene Oxide: A Hybrid Material for Cancer Cell Detection through Hydrogen Peroxide Sensing, ACS Appl. Mater. Interfaces, 2014, 6, 13648–13656. Copyright© American Chemical Society.] (D) Schematic of the rGO-PtNPs-modified GCE for detecting H2O2 efflux from cells stimulated with ascorbic acid (AA). [Reprinted with permission from ref. 381, Y. Zhang, X. Bai, X. Wang, K.-K. Shiu, Y. Zhu and H. Jiang, Highly Sensitive Graphene–Pt Nanocomposites Amperometric Biosensor and Its Application in Living Cell H2O2 Detection, Anal. Chem., 2014, 86, 9459–9465. Copyright© American Chemical Society.] (E) Schematic of the rGO/AuFe3O4/PtNPs-modified GCE for detecting H2O2 efflux from cells stimulated with ascorbic acid (AA). (F) Amperometric response upon adding AA in PBS containing HeLa cells at 0 V (red), containing HeLa cells and catalases (blue), or without cells (green). (G) Amount of H2O2 released by L02, HeLa, HepG2, and U87 cells stimulated by 1 μM AA. [Reprinted with permission from ref. 382, L. Wang, Y. Zhang, C. Cheng, X. Liu, H. Jiang and X. Wang, Highly Sensitive Electrochemical Biosensor for Evaluation of Oxidative Stress Based on the Nanointerface of Graphene Nanocomposites Blended with Gold, Fe3O4, and Platinum Nanoparticles, ACS Appl. Mater. Interfaces, 2015, 7, 18441–18449. Copyright© American Chemical Society.].
