On the response of a label-free interferon-γ immunosensor utilizing electrochemical impedance spectroscopy

Logarithmic dose-response curves of IFN-γ in the concentration range of 10−18 to 10−9 M were obtained using two procedures: by successive injections over a single electrode, and by using freshly prepared electrodes for each measurement. Using the latter method, the repeatability is impaired. The need for in situ complementary techniques for a correct interpretation of the studied parameters is discussed.