Enzyme‐free Recycling Amplification‐based Sensitive Electrochemical Thrombin Aptasensor

Abstract

Abstract In this work, an enzyme‐free recycling amplification‐based sensitive electrochemical thrombin aptasensor using catalytic hairpin assembly (CHA) and bisferrocene was proposed for electrochemical beacon. Thrombin triggered the CHA reaction that in turn formed a number of double‐stranded complexes,which are fixed on the surface of the gold electrode through potential‐assisted Au−S deposition, and a large number of labeled bisferrocene are placed close to the gold electrode to generate electrochemical signal. The linear range of the electrochemical sensor was 0.25 pM‐2.5 nM for thrombin with detection limit of 0.18 pM. This sensor can be employed to monitor the thrombin in human serum samples.