A label-free electrochemical aptasensor based on leaf-like vanadium disulfide-Au nanoparticles for the sensitive and selective detection of platelet-derived growth factor BB

In this work, an electrochemical aptasensor for the sensitive detection of platelet-derived growth factor BB (PDGF-BB) is fabricated based on leaf-like VS2 nanosheets which are prepared by a facile hydrothermal method. The scanning electron microscopy and transmission electron microscopy images demonstrate that the as-prepared VS2 is constructed with many irregular sheets in a leaf-like structure with a thickness of several nanometers. The electrochemical aptasensor is constructed by depositing Au nanoparticles (AuNPs) on the VS2 nanosheet modified glassy carbon electrode and then immobilizing the aptamer. Using the AuNP/VS2 composite as the sensing platform greatly enhances the effective surface area of the electrode and thus amplifying the detection response. The proposed aptasensor can sensitively detect PDGF-BB with a low detection limit of 0.4 pM and over a wide target concentration range of 0.001 nM to 1.0 nM. The aptasensor has been successfully applied in the determination of PDGF-BB in human urine samples and the results compared well with those by the reference ELISA method, indicating its promise in biochemical analysis.