Device for measuring proteins using biosensor

A method of measuring a concentration of a specific protein using a biosensor comprising:

• feeding a sample comprising the specific protein into a biosensor;
• wherein the biosensor comprises a sample inlet through which the sample is drawn in, a working electrode on which a receptor layer is coated for selective binding to the specific protein in the drawn sample, and a measuring unit comprising a reference electrode to form a potential difference with the working electrode,
• applying a potential signal in a form of delta function waveform to the working electrode and the reference electrode;
• and
• measuring an impedance of the working electrode by Fourier-transforming an electric current obtained in response to the delta function waveform.