Time-resolved, label-free electrochemical monitoring of neurotoxicity via differential pulse voltammetry

Neurotoxicity assessment is crucial for ensuring the safety of pharmaceuticals and chemicals while protecting public health by identifying hazardous substances. Here, a simple and innovative electrochemical neurotoxicity assay was presented using a screen-printed carbon electrode (SPCE) integrated petri dish platform. This system serves as a rapid, quantitative, and time-resolved alternative to standard neurotoxicity assays such as the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test and is particularly suited for drug development studies. Briefly, the surface of SPCEs were modified with poly-l-lysine (PLL) to enhance both the electrochemical signal and the adherence of human neuroblastoma (SH-SY5Y) cells. Electrochemical measurements were taken in 0.5 mM [Fe(CN)₆]^3-/4- whose non-toxic effect was confirmed, and a good relationship was observed between electrochemical signal and cell viability. The electrochemical platform was then successfully tested to assess the toxic effects of H₂O₂ and doxorubicin. These findings demonstrate the platform's potential for routine electrochemical neurotoxicity evaluation and emphasize the feasibility of using a cell-based analytical system for toxicity screening applications.