Synergistic pH effect for reversible shuttling aptamer-based biosensors between graphene oxide and target molecules

Abstract

DNA aptamers are known to desorb from graphene oxide (GO) surface in the presence of target molecules. We demonstrate herein that the binding equilibrium can be shifted by simply tuning the solution pH. At lower pH, the aptamer/GO binding is enhanced while aptamer/target binding is weakened, making this system a regenerable biosensor without covalent conjugation.