Green synthesis of nonprecious metal-doped copper hydroxide nanoparticles for construction of a dopamine sensor

Background: Copper oxide nanoparticles doped with nonprecious metal species (Ni and Mn) were synthesized. Method: A glassy carbon electrode (GCE) was modified by drop-casting of nanostructure suspensions, constructing Ni:Cu(OH) 2 /GCE, Mn:Cu(OH) 2 /GCE and Cu(OH) 2 /GCE. Results: The voltammetric oxidation of dopamine (DA) by the constructed electrodes confirmed that the electrocatalytic oxidation of DA is a reversible, pH-dependent, diffusion-controlled process; the best response was obtained by Mn:Cu(OH) 2 /GCE. A sensitive calibration graph (0.664 μA/μM) was produced for DA in the concentration range of 0.3–10.0 μM, with a detection limit of 79 nM using Mn:Cu(OH) 2 /GCE. Conclusion: The Mn:Cu(OH) 2 /GCE possessed an accurate response toward DA with an acceptable selectivity, stability and antifouling effect, revealing the applicability of the Mn:Cu(OH) 2 /GCE for DA analysis in biological samples.