title: Electrochemical immunosensor for α-fetoprotein detection using ferroferric oxide and horseradish peroxidase as signal amplification labels.
abstract: An electrochemical immunosensor for quantitative detection of α-fetoprotein (AFP) in human serum was developed using graphene sheets (GS) and thionine (TH) as electrode materials and mesoporous silica nanoparticles (MSNs) loaded with ferroferric oxide (Fe3O4) nanoparticles and horseradish peroxidase (HRP) as labels for signal amplification. In this study, the compound of GS and TH (GS-TH) was used as a substrate for promoting electron transfer and immobilization of primary antibody of AFP (Ab1). MSNs were used as a carrier for immobilization of secondary antibody of AFP (Ab2), Fe3O4, and HRP. The synergistic effect occurred between Fe3O4 and HRP and greatly improved the sensitivity of the immunosensor. This method could detect AFP over a wide concentration range from 0.01 to 25 ng ml(-1) with a detection limit of 4 pg ml(-1). This strategy may find wide potential application in clinical analysis or detection of other tumor markers.
authors.affiliation: School of Materials Science and Technology, China University of Geosciences, Beijing 100083, People's Republic of China.
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
authors.forename: Kexia
authors.initials: K
authors.lastname: Mao
authors.affiliation: School of Materials Science and Technology, China University of Geosciences, Beijing 100083, People's Republic of China; Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China.
authors.forename: Bin
authors.initials: B
authors.lastname: Du
authors.affiliation: School of Materials Science and Technology, China University of Geosciences, Beijing 100083, People's Republic of China. Electronic address: zyh@cugb.edu.cn.
authors.forename: Yihe
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Chemical Sensing and Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, People's Republic of China. Electronic address: sdjndxwq@163.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
mesh_terms: D055664:Electrochemical Techniques / Q000379:methods*; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006735:Horseradish Peroxidase / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis*
chemical_list: D058185:Magnetite Nanoparticles; D000509:alpha-Fetoproteins; D006735:Horseradish Peroxidase; D052203:Ferrosoferric Oxide
keywords: Graphene; Horseradish peroxidase; Immunosensor; Mesoporous silica nanoparticles; α-Fetoprotein