Aptamers are a specific class of ligands with high affinities comparable to antibodies, which are selected and synthesized in vitro. In combination with impedance spectroscopy as sensitive measurement method, we gain a class of biosensors with high potential for handheld devices and point-of-care tests. In this review, we report on recent advances in aptamer-based impedimetric biosensors. Besides giving a short summary of electrochemical measurement techniques, the most exciting innovative developments of detection strategies in the last decades are reviewed. Finally, important criteria for the comparison of aptamer-based biosensors are discussed.
Keywords: Aptamer; Aptasensor; Biosensor; Capacitive; DNA origami; Electrode; Faradaic; Impedance; Label-free; Nanocomposites; Nanotechnology; Non-faradaic; Rapid detection; Redox mediator.