Preparation of Au/α‐Fe₂O₃ Electrode for the Detection of Dopamine

In this study, Au/α‐Fe 2 O 3 sensing material was synthesized and used as the working electrode for dopamine sensing. The Au/α‐Fe 2 O 3 composites were prepared with various loadings (0.5 %, 1 %, and 3 %) to enhance their sensing properties. All three composites were tested for dopamine sensing, with 1 % Au/α‐Fe 2 O 3 showing the best response. The Au/α‐Fe 2 O 3 composites were characterized using XRD, TEM, and SEM to confirm successful doping of Au on the iron oxide surface. The CV plot obtained by plotting Cyclic Voltammetry (CV) vs. dopamine (DA) was linear (R 2 =0.9872) for DA concentrations ranging from 6.25 μM–200 μM on 1 % Au/α‐Fe 2 O 3 . Similarly, the DPV plot between DPV vs. DA was linear (R 2 =0.9895) for the same DA concentration range on 1 % Au/α‐Fe 2 O 3 , with a detection limit of 0.19 μM. Interference and stability experiments were conducted with dopamine (DA), ascorbic acid (AA), and uric acid (UA). The results showed that DA sensing was not affected by the other two substances for up to 14 days. The signal results indicated that the current intensity remained at 90.75 % of the original, proving that this material has good stability.