Electrosynthesis of copper particles at nanoporous poly(3,4-ethylenedioxythiophene) for glutathione electroanalysis in microglia cell lysates

• Controllable template free electrosynthesis of copper particles on nanoporous PEDOT • Glutathione (GSH) quantitation as an important biomarker in ferroptosis • GSH-copper complexation exploited as quantitative redox signal • Excellent electrochemical performance in cell lysate matrix . Here, the rapid and controllable in situ electrosynthesis of copper particles on conducting polymer supports realised determination of the biological thiol glutathione (GSH) using a simple two step electrode fabrication approach. Suppression of the copper redox signal as a result of the high chemical affinity of copper and GSH resulted in a quantitative response in the range 20 to 200 µmol L −1 , sensitivity 0.375 ± 0.03 µA µmol L −1 with detection limit of 3.27 µmol L −1 . Signal robustness, low operating potential (E = 0.01 V vs Ag | AgCl) and reproducibility (6.7% and 0.25% RSD for inter and intra electrode precision respectively, n=10) were strong characteristics of the sensor performance. The methodology was applied to cell lysates of murine BV2 cells, as a well-characterised in vitro model of mammalian microglial cells. .