Enhanced electrochemical biosensing of alpha-fetoprotein based on three-dimensional macroporous conducting polymer polyaniline

• DOI: 10.1016/j.snb.2017.09.062
• Publication Date: 2017-09-10T14:31:13Z
• Authors: Shuo Liu; Yihui Ma; Min Cui; Xiliang Luo
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract A sensitive and selective electrochemical sensor for the determination of alpha-fetoprotein (AFP) was developed based on the three-dimensional (3D) macroporous polyaniline (PANI) doped with poly(sodium 4-styrene sulfonate) (PSS) by using a hard-template method. The 3D macroporous PANI possessed large surface area, high conductivity and many functional groups, and it provided an excellent substrate for the immobilization of alpha-fetoprotein (AFP) antibodies to construct an electrochemical biosensor. Based on the measurement of the inherent redox signal change of the porous PANI, the prepared AFP immunosensor was reagentless and it exhibited satisfying sensing performances toward its target AFP. Under optimum conditions, the porous PANI-based immunosensor achieved a wide linear range for AFP from 0.01 to 1000 pg mL −1 , with a detection limit of 3.7 fg mL −1 . Significantly, the response sensitivity of this sensor was about 2 times higher than that of the planar PANI-modified electrode, manifesting a great enhancement effect associated with the 3D macroporous structure.