DNA-Generated Electric Current Biosensor for Epidermal Growth Factor Receptor 2 (HER2) Analysis

Electrochemical biosensors have been applied in the detection of human serum biomarkers for clinical applications. A kind of signal amplifying method using deoxyribonucleic acid (DNA) as signal probe was developed to construct electrochemical biosensor for biomarker detection. In addition to its primary function as genetic material, DNA is also a potential source of molecular electronics that generate redox currents. As an example of this new function, DNA-generated redox currents were used for electrochemical detection of human epidermal growth factor receptor 2 (HER2), a clinically important biomarker for breast cancer. In order to induce the redox current, the phosphate backbone of the single-stranded DNA was reacted with molybdate to form redox molybdophosphate precipitate and generate electrochemical current. Within a certain range, the peak current is linearly proportional to the concentration of HER2, thus realizing the quantitative analysis of HER2 in human serum.