Ruthenium Nanoparticle-Immobilized Porous Carbon Nanofibers for Nonenzymatic Dopamine Sensing

Abstract

Dopamine (DA) is a type of neurotransmitter that plays an important role in the functions of the central nervous system, as well as renal, hormonal, and cardiovascular systems. In particular, abnormal changes in dopamine concentrations could cause serious diseases such as sleeping and eating disorders, Parkinson's disease, and addictive behaviors associated with drug abuse. However, it is difficult to detect the change in concentration level in a reliable manner when it is present in extremely small levels. In this study, we suggested a ruthenium nanoparticle-immobilized multiscale pore-containing carbon nanofiber (Ru-MPCNF)-based field-effect transistor (FET) nonenzymatic sensor to detect DA. Ru-MPCNF was generated as an active material to target analyte using single-nozzle co-electrospinning and an oxygen plasma method to obtain a uniformly immobilized Ru component in the carbon structure. The porous carbon structure not only promotes the generation of small-size Ru particles but also induces a large active surface area for dopamine. The nonenzymatic sensor electrode showed high sensitivity to DA as low as 1 fM, even in the presence of interfering biomolecules. Moreover, the sensor electrode also displayed stable sensing performance with long lifetimes due to the nonbiological working mechanism.