An ultrasensitive universal detector based on neutralizer displacement

A universal detector of small molecules, proteins and nucleic acids is described that relies on the displacement of a neutralizer molecule from a sensor surface. When the neutralizer is displaced by an analyte, an electrochemical signal is generated. Ultrasensitive limits of detection are achieved, and a new record for the electrochemical detection of bacteria (0.15 colony-forming units per microlitre) is reported.