Electrochemical biosensor for epidermal growth factor receptor detection with peptide ligand

Epidermal growth factor receptor (EGFR) that has been over-expressed in many different types of cancers has become logical targets for both diagnosis and therapy. Herein, we report an electrochemical peptide-based biosensor for the detection of EGFR, in which ferrocene moiety modified peptide ligands that are specific to EGFR were immobilized on gold electrode through Au-S interaction. Upon the binding of peptide ligands with EGFR, complex formation changes occurred on the electrode surface, which resulted in current increase. The amplitude of the current increase displayed a linear relationship with logarithm of the EGFR concentrations in the range of 1.0 × 10−6-1.0 × 10−10 g L−1, with a detection limit of 3.7 × 10−11 g L−1. The proposed method has been applied for determination of EGFR in diluted human serum samples with satisfied results.