Graphdiyne: A new promising member of 2D all-carbon nanomaterial as robust electrochemical enzyme biosensor platform

Graphdiyne (GDY), a new two-dimensional all-carbon allotrope composed of benzene rings and alkyne unites, was successfully synthesized via a crossing-coupling reaction with much intriguing properties especially highly pi-conjugated structure, attractive electronic and chemical properties, good biocompatibility and dispersion in aqueous solution. The as-prepared graphdiyne was explored for the first time as an extremely attractive matrix for tyrosinase (a model enzyme) immobilization to construct a mediator-free GDY-based biosensor for rapid detection of bisphenol A (BPA). The response of GDY-based tyrosinase biosensor is linear over the range of 1.0 x 10(-7) to 3.5 x 10(-6) mol L-1 with a high sensitivity of 2990.8 mA cm(-2)M(-1) and a low detection limit of 24 nmol L-1. The proposed GDY-based tyrosinase biosensor exhibited better analytical performances for BPA detection than CNTs and graphene based biosensors. The excellent performance of the biosensor should partially be ascribed to the strong pi-pi interactions between graphdiyne and BPA, which could enrich available BPA concentration on the electrode to react with tyrosinase. The robust GDY-based tyrosinase biosensor was used for BPA detection in drinking bottles and tap water with satisfactory results. As a new 2D all-carbon nanomaterial, graphdiyne is proved to be a powerful electrochemical enzyme biosensor platform for biomolecules (as recognition elements) immobilization and biosensor fabrication, and provides great application prospect for biomedical detection and environmental analyses. (C) 2019 Elsevier Ltd. All rights reserved.