We report unprecedented ultra high frequency capacitance spectroscopy measurements up to 500 MHz on a nanoelectrode array for biosensing applications, which extends considerably the previous 70 MHz limit. To achieve this goal, a high-frequency adapter board and measurement system are designed to drive the sensing nanoelectrodes of an existing biochip with appropriate clocks generated by an advanced high-speed pulser. Experimental results in dry and in electrolyte conditions are reported. The extended frequency range enables to overcome the Debye screening cut-off frequency of electrolytes at physiological salt concentrations, thus disclosing new perspectives for single molecule detection.
