Detection of adherent cells using electrochemical impedance spectroscopy based on molecular recognition of integrin β1

Mouse anti-human integrin β1 monoclonal antibody was assembled on glass carbon electrode by layer-by-layer adsorption. The determination of cervical cancer HeLa cells was performed using electrochemical impedance spectroscopy based on the immunoreaction between integrin β1 on cell membrane and the antibody immobilized on the electrode-surface. The factors influencing cell-detection, such as the concentration of gold nanoparticles in the modified film, the drying time of the modified film, the concentration of antibody and the binding time of antibody, were investigated, respectively. Under optimum conditions, the increasing extent of electrode-transfer resistance depended linearly on the cell concentration in the range of 1.0 × 104 to 2.0 × 106 cells mL−1 with a detection limit of 3.5 × 103 cells mL−1.