Fabrication of non-destructive and enhanced electrochemiluminescence interface for reusable detection of cell-released dopamine

Quantification of cell-released dopamine (DA) is essential to understand various biological processes. However, concentration of DA outside living cells may increase and decrease in a short time. Thus, approaches used to detect cell-released DA should meet higher demands. Herein, a simple and green method is employed to in situ growth of gold nanoparticles on the surface of WS₂ nanosheets. The defects of prepared Au-WS₂ nanocomposites may accelerate electron transfer and facilitate the absorption of dissolved oxygen. As a result, Au-WS₂ nanocomposites-enhanced electrochemiluminescence (ECL) is observed for the first time, and is further used to fabricate a non-destructive and label-free analytical interface. The ECL interface can selectively detect DA in a range of 5.0 nM–200 μM with a detection limit of 3.23 nM. Meanwhile, since the architecture on the ECL interface is not destroyed during the detection procedure, DA can be quantified continuously at least six times after one fabrication. In addition, the proposed ECL interface can accurately monitor the release of DA from PC12 cells manipulated by K⁺ and nifidipine, indicating great potential of this ECL sensor for surveying DA-related investigations.