An impedimetric single-shot assay is described for the determination of the proteinic breast cancer marker MUC1. The surface of a glassy carbon electrode was modified with core-shell nanofibers, multi-walled carbon nanotubes and gold nanoparticles that were covalently modified with the MUC1-binding aptamer. Detection is based on the change of the resistance of the electrode surface as measured by electrochemical impedance spectroscopy using hexacyanoferrate(II/III) as an electrochemical probe in working potential is 0.25 V. Scanning electron microscopy and cyclic voltammetry were also applied to characterize the electrode. The analytical response ranges from 5 to 115 nM of MUC1, with a detection limit of 2.7 nM. The assay was successfully applied to MUC1 determination in spiked serum samples where it gave satisfactory results. Graphical abstractAn impedimetric nanoprobe for the tumor marker MUC1 is proposed. It is based on use of electrospun honey core-shell nanofibers. The nanoprobe exhibits excellent sensitivity, good stability and a low detection limit.
Keywords: Electrochemical detection; Electrochemical impedance spectroscopy; Electrospinning; Gold nanoparticles; Multi-walled carbon nanotubes; Nanoprobe.