CNT Wiring for Signal Amplification in Electrochemical Magnetosensors

Abstract

Magnetic particles (MPs) are useful tools for analyte binding and concentration, which has been extensively exploited for the development of electrochemical magnetosensors. Here, after binding and washing, MPs are wrapped with carbon nanotubes (CNT) and layered onto an electrode. In this way, CNT wiring provides signal amplification in subsequent electrochemical detection. We demonstrate this approach by accomplishing dopamine detection and myeloperoxidase (MPO) enzymatic activity monitoring. For dopamine detection, dopamine is electrostatically bound using streptavidin-MPs and for MPO enzymatic activity monitoring, immunofunctionalized MPs and commercially available tetramethylbenzidine-based (TMB) enzymatic substrate are used.