The use of a signal amplification strategy for the fabrication of a TNT impedimetric nanoaptasensor based on electrodeposited NiONPs immobilized onto a GCE surface

Abstract

This study reports on the evaluation of NiONPs layer as an efficient platform in designing a TNT nanoaptasensor. Based on this strategy, a film of electrodeposited NiONPs was immobilized onto the surface of a GCE. This film was used as a capture layer for the covalent attachment of Apt, which was a receptor element with regard to TNT. By incubating TNT onto the surface of the prepared Apt/NiONPs/GCE as a proposed nanoaptasensor, the Apt/TNT complex was formed and the changes of the electrochemical signal were evaluated with the EIS technique. The superior transduction platform and the Apts were densely populated at the surface of the modified electrode lowered the LOD, 33.5aM. Furthermore, the excellent antifouling ability of the NiONPs/GCE improves the operational stability and repeatability of the proposed nanoaptasensor. While most of the conventional approaches have used multistep chemical methods for modeling an apasensor, our proposed strategy provides the notable advantages the use of a single-step modification without employing any complex agent, the use of a simple procedure and not being time-consuming. The results indicated that the modification of a GCE with the electrodeposited NiONPs layer can expand the application of this strategy to develop some biosensors based on DNA in order to detect various targets.