Coral-like hierarchical structured carbon nanoscaffold with improved sensitivity for biomolecular detection in cancer tissue

Abstract The development of flexible microelectrodes with large surface area and high activity has currently attracted enormous research interest for its promising use in in vitro and in vivo monitoring various physiological behaviors. Inspired by the unique morphological and structural features of dendritic coral, a coral-like hierarchical nanohybrid of carbon nanospheres (GNSs) wrapped hollow carbon tubes (HCT) has been designed and modified on flexible activated carbon fiber (ACF) microelectrode for sensitive electrochemical detection of biomarker in live cells and cancer tissue. The hierarchical nanohybrid microelectrode was fabricated by a novel dual-template strategy using ZnO nanorod arrays as the hard template and poly-glucose microspheres as both self-template and carbon source, which results in the formation of coral-like structured carbon nanoscaffold integrated with GNSs wrapped HCT hybrids (HCT@GNSs) on ACF substrate for homogeneous interfacial contacts and reaction. The as-obtained HCT@GNSs modified ACF (HCT@GNSs/ACF) microelectrode exhibits high specific surface area and good stability, and serves as an ideal support for anchoring functional nanomaterials. In order to improve the electrochemical activity of the modified microelectrode, HCT@GNSs has been decorated with dense and ultrafine Pt nanoparticles (PtNPs). Benefiting from the hierarchical feature of HCT@GNSs and uniformly distribution of electroactive PtNPs, the PtNPs decorated HCT@GNSs/ACF microelectrode demonstrates good electrochemical sensing performance toward H2O2, which enable the operating electrochemical platform be used for real-time tracking H2O2 generated from different types of live cells and in situ sensitive detection of H2O2 in cancer tissue from laboratory mice.