Fluorophore-Induced Plasmonic Current Based Detection of Aqueous Fe3+Ions Using a Turn-OnFluorescence Probe and Copper Nanoparticle Substrates

In this paper, we report on one of the first applications of fluorophore-induced plasmonic current (FIPC) developed, namely, the direct detection of analytes using turn-onfluorescent sensing probes. Recent work by our group has demonstrated the utility of various types of metal nanoparticle films and how these different films can provide the suitable spectral overlap for a wide range of fluorophores and chromophores to be directly detected “electrically”. In this article, we subsequently share our findings pertaining to the sensing of aqueous Fe3+ions via a turn-on fluorescent probe. The probe’s responses are compared between their typical fluorescence solution-based responses as well as their ability to sense Fe3+via the new FIPC transduction mechanism. Our results suggest a pathway for the development of FIPC-based detection of analytes vs using traditional fluorescence sensing techniques, albeit, with nearly identical sensing instrumentation.