Structure-switching hairpin probe based electrochemical aptasensor for highly sensitive detection of protein

Abstract

Using platelet derived growth factor B chain (PDGF-BB) as the model analyte, a structure-switching hairpin probe based electrochemical biosensing strategy for highly sensitive detection of protein is proposed in this work.Aptamer probe hybridized with the immobilized hairpin structured signal probe to form DNA duplex.Upon binding with target protein, competition between target molecule and the signal probe with the aptamer probe happened, inducing the signal probe from stretched duplex to hairpin structure.Under optimum experimental conditions, the target protein can be sensitively detected in a linear dynamic range from 0.1 ng/mL to 500 ng/mL with a low detection limit of 0.08 ng/mL.