Biosensor based on bimetallic/graphene composite for non-enzymatic detection of hydrogen peroxide in living tumor cells.

A highly sensitive electrochemical biosensor was manufactured with triple synergistic catalysis to detect hydrogen peroxide (H2 O2 ). In this study, a highly sensitive biosensor based on Prussian blue-chitosan/graphene-hemin nanomaterial/platinum and palladium nanoparticles (PB-CS/HGNs/Pt&Pd biosensor) was fabricated for the detection of H2 O2 . The materials described above were modified on the electrode surface and applied to catalyze the breakdown of hydrogen peroxide. The current response of the biosensor presented a linear relationship with H2 O2 concentration from 6 × 10-2 to 20 µM (R2 = 0.9766) and with the logarithm of H2 O2 concentration from 20 to 9×103  µM (R2 = 0.9782), the low detection limit of 25 nM was obtained at the signal/noise (S/N) ratio of 3. Besides, the biosensor showed an outstanding anti-interference ability and acceptable reproducibility. PB-CS/HGNs/Pt&Pd electrodes are effective in measuring H2 O2 from living tumor cells, which implies that the biosensor has the potential to assess reactive oxygen species in various living tumor cells.