Highly dispersed gold nanoparticles anchoring on COFTAPB-DMTP for electrochemical detection of paracetamol

Abstract

Small size Au nanoparticles (AuNPs) have aroused wide interest in electrochemical sensing due to its high surface atom utilization and superior electrical conductivity. However, there was a great challenge to balance the stability and small-size of AuNPs because of their large specific surface and high surface energy. Regarding this issue, herein, COF_TAPB-DMTP was proposed as guiding support substrate for the synthesis of highly dispersed and small size AuNPs, where the uniform functional sites such N, O atoms on COF_TAPB-DMTP could act as anchor points to induce in-situ reduction of AuNPs, and the confinement effects from the nanopore of COF_TAPB-DMTP could limit their size. Then, an electrochemical paracetamol (PA) sensor was designed based on AuNPs@COF_TAPB-DMTP since the abundant active centers and outstanding electrical conductivity of highly dispersed small size AuNPs conferred the composite excellent sensing performance. Moreover, the large specific surface, ordered pore channels and abundant heteroatomic functional groups of COF_TAPB-DMTP could achieve high enrichment capacity toward PA molecules on electrode surface through pore effect, hydrogen bonding and electrostatic interaction. Benefiting from the combination between AuNPs and COF_TAPB-DMTP, the AuNPs@COF_TAPB-DMTP based sensor presents excellent analytical performance in term of low limit of detection (22 nM), satisfactory stability, reproducibility and selectivity. It indicated that COFs can be used as promising inducible substrate material for the preparation of highly dispersed and small size metal nanoparticles.