A novel non-enzymatic electrochemical biosensor based on the nanohybrid of bimetallic PdCu nanoparticles/carbon black for highly sensitive detection of H2O2 released from living cells

Hydrogen peroxide (H2O2) is a major metabolite of oxygen known as reactive oxygen species (ROS) in living organisms. Monitoring H2O2 released from living cells is of great significance as its concentration level is related to several diseases, which imposes stricter requirements on the sensitivity of detection technology. In this work, we have found that carbon black (CB) could preserve bimetallic PdCu alloy's nanostructure, meanwhile improve the dispersion of nanoparticles, provided high conductivity and large specific surface area, thus the PdCu/CB nanohybrid exhibited enhanced electroanalytical performance of H2O2. Under the optimal conditions, the PdCu/CB nanohybrid modified electrode showed a low detection limit of 54 nM with a wide detection range from 0.4 mu M to 5.0 mM. Finally, the application of PdCu/CB/GCE in real-time monitoring H2O2 released from Raw 264.7 cells was achieved, suggesting the PdCu/CB nanohybrid was the promising nanomaterial in monitoring physiological processes.