The fabrication of gold nanoelectrode-nanopore nanopipette for dopamine enrichment and multimode detection
It is important to further improve the electrophysiology and electrochemistry techniques of neurotransmitter detection. Here, we report the development of multifunctional nanopipette-based integrated approaches for the detection of neurotransmitters. We successfully fabricated a nanopipette with two independent functional units at the apex, a nanopore and a gold nanoelectrode (GNE). The GNE shows good electrochemical reponse to dopamine (DA). Further, both the nanopore and nanoelectrode can effectively enrich dopamine (DA) but not ascorbic acid by electrical means. The enriched DAs are then detected and analyzed with obviously improved signal-to-noise ratio by electrochemical methods and Surface-enhanced Raman spectroscopy (SERS). In addition, with the addition of silver nanoparticles during enrichment, up to 10 times increase of Raman intensity of DA can be observed.