Electrochemical and electrochemiluminescent behaviors of a single Nafion@Ru or Au-Nafion@Ru nanoparticle colliding onto an ultramicroelectrode

Abstract

Nafion and Au-Nafion nanoparticles (NPs) are electrostatically loaded with ruthenium (II) tris(2,2’-bipyridyl) (Ru(bpy)32+) luminescent molecules to prepare Nafion@Ru and Au-Nafion@Ru NPs. The average spike current, peak charge and duration per spike of the response peaks generated by random collisions of Au-Nafion@Ru NPs and Nafion@Ru NPs on gold ultramicroelectrodes (Au UME) were analyzed and compared, and an electrochemical collision system with Au-Nafion@Ru NPs as the main body was established. The results show that the prepared Au-Nafion@Ru NPs possess the special structure of Au-Nafion@Ru, which can increase the effective contact or collision sites between NPs and Au UME with the co-participation of Nafion and AuNPs, resulting in an enhanced electrochemical collision response signal. In the system of Au-Nafion@Ru NPs-tri- n -propylamine (TPrA), the time-current curve and electrochemiluminescence (ECL)-time method were used to monitor the electrical and ECL transient signals generated by Nafion@Ru or Au-Nafion@Ru NPs colliding with Au UME, and a good relationship between electrochemical and ECL transient signals generated by the collisions of single Au-Nafion@Ru NPs-TPrA on Au UME was established. This strategy provides a new insight for studying the electrochemical collision systems of other molecules.