An Electrochemical Immunosensor with Graphene‐Oxide‐Ferrocene‐based Nanocomposites for Hepatitis B Surface Antigen Detection

Abstract

Abstract The detection of hepatitis B surface antigen (HBsAg), a coat protein secreted by hepatitis B virus, is a common method for confirming infection in early diagnosis. A new composite of graphene oxide‐ferrocene‐chitosan (GO‐Fc‐CS) was synthesized and used to develop an electrochemical immunosensor with a GO‐Fc‐CS/Au‐nanoparticle layer film for HBsAg detection. The modified layer film exhibited not only enhanced electron conductivity, but also strong reversible redox signal for current changes, excellent biocompatibility, and good film‐forming ability for binding a large number of antibodies. The immunosensor exhibits a wide linear range from 0.05 to 150 ng/mL and detection limit of 0.01 ng/mL for HBsAg. The excellent performance in HBsAg detection suggests that the proposed immunosensor has potential application in clinical diagnosis.