An apparatus for the diagnosis of a biological sample is disclosed. An embodiments of the apparatus includes a probe, a probe head distally connectable to the probe, the probe head further comprising a plurality of electrode elements thereby forming an electrode array where each electrode element is variably actuatable to apply an electrical signal to the biological sample; an RF signal source for applying the electrical signal to the electrode array; an electrode selector adapted and configured to switch the electrical signal from the RF signal source between the plurality of electrode elements; and a detection circuit for analyzing a dielectric property received from the biological sample. Methods and kits for diagnosing a biological sample are also disclosed.