Sensitive electrochemical immunosensor for α-fetoprotein based on graphene/SnO2/Au nanocomposite

• Published in: Biosensors & bioelectronics Vol. 71; pp. 82 - 87
• Main Authors: Liu, Junfeng, Lin, Guanhua, Xiao, Can, Xue, Ying, Yang, Ankang, Ren, Hongxuan, Lu, Wensheng, Zhao, Hong, Li, Xiangjun, Yuan, Zhuobin
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 15.09.2015
• Subjects: alpha-Fetoproteins - analysis; Antibodies; Biosensing Techniques - methods; Biosensors; Electrochemical immunosensor; Electrochemical Techniques - methods; Electrodes; Gold - chemistry; Graphene; Graphite - chemistry; Humans; Immunoassay - methods; Immunosensors; Limit of Detection; Nanocomposite; Nanocomposites; Nanocomposites - chemistry; Nanocomposites - ultrastructure; Tin Compounds - chemistry; Tin dioxide; Tin oxides; α-Fetoprotein; Electrochemical immunosensor; Nanocomposite; α-Fetoprotein; Graphene
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2015.04.012

A label-free electrochemical immunosensor for sensitive detection of α-fetoprotein (AFP) was developed based on graphene/SnO2/Au nanocomposite. The graphene/SnO2/Au nanocomposite modified glassy carbon electrode was used to immobilize α-fetoprotein antibody (anti-AFP) and to construct the immunosensor. Results demonstrated that the peak currents of [Ru(NH3)6]3+ decreased due to the interaction between antibody and antigen on the modified electrode. Thus, a label-free immunosensor for the detection of AFP was realized by monitoring the peak current change of [Ru(NH3)6]3+. The factors influencing the performance of the immunosensor were investigated in details. Under optimal conditions, the peak currents obtained by DPV decreased linearly with the increasing AFP concentrations in the range from 0.02 to 50ngmL−1 with a linear coefficient of 0.9959. This electrochemical immunoassay has a low detection limit of 0.01ngmL−1 (S/N=3) and was successfully applied to the determination of AFP in serum samples. •A novel ternary graphene/SnO2/Au was synthesized.•High sensitive and label-free electrochemical immunosensor for detection of α-fetoprotein was developed.•The proposed electrochemical immunosensor was successfully applied to the determination of AFP in serum samples.