▎ 摘　　要

Balancing electrostatic repulsive force and bonding interactions are the key principles for constructing 3D graphene architecture on single carbon fiber (CF). Herein, we present a simple and facile method to modify 3D porous N, B co-doping graphene on single CF (CF@3D-NBG). In the process, the Ni nanoparticles were deposited on CF and used as a reductant for reducing graphene oxide (GO), promising graphene-wrapped CF at low temperature. Ionic liquids were introduced to prevent re-aggregation of graphene sheets during the reduction process of GO, but also acted as heteroatom sources for doping graphene, which provides high electrical conductivity, numerous doping sites and edges for H2O2 electrocatalysis reduction. It is found that the CF@3D-NBG flexible microelectrodes show a broad linear range from 0.5 mu M to 4.25 mM and a low detection limit of 100 nM for H2O2 detection. When applied to track the amount of H2O2 generated from real samples, the sensor exhibits desirable performance in distinguishing cancer cells from normal cells and further assessing the therapeutic effect of antitumor drugs on live cancer cells. Therefore, this study may offer an attractive method for synthesizing advanced graphene-based electrodes with great promise for biosensors.