title: Facile fabrication of an ultrasensitive sandwich-type electrochemical immunosensor for the quantitative detection of alpha fetoprotein using multifunctional mesoporous silica as platform and label for signal amplification.
abstract: A novel and ultrasensitive sandwich-type electrochemical immunosensor was designed for the quantitative detection of alpha fetoprotein (AFP) using multifunctional mesoporous silica (MCM-41) as platform and label for signal amplification. MCM-41 has high specific surface area, high pore volume, large density of surface silanol groups (SiOH) and good biocompatibility. MCM-41 functionalized with 3-aminopropyltriethoxysilane (APTES), gold nanoparticles (Au NPs) and toluidine blue (TB) could enhance electrochemical signals. Moreover, primary antibodies (Ab1) and secondary antibodies (Ab2) could be effectively immobilized onto the multifunctional MCM-41 by the interaction between Au NPs and amino groups (-NH2) on antibodies. Using multifunctional MCM-41 as a platform and label could greatly simplify the fabrication process and result in a high sensitivity of the designed immunosensor. Under optimal conditions, the designed immunosensor exhibited a wide liner range from 10(-4) ng/mL to 10(3) ng/mL with a low detection limit of 0.05 pg/mL for AFP. The designed immunosensor showed acceptable selectivity, reproducibility and stability, which could provide potential applications in clinical monitoring of AFP.
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Yulan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
authors.affiliation: School of Chemical Engineering, Shandong University of Technology, Zibo 255049, PR China.
authors.forename: Yueyun
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Du
authors.affiliation: Key Laboratory of Chemical Sensing & Analysis in Universities of Shandong, School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China. Electronic address: sdjndxwq@163.com.
authors.forename: Qin
authors.initials: Q
authors.lastname: Wei
mesh_terms: D055910:Antibodies, Immobilized / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques; D004563:Electrochemistry / Q000379:methods*; D006046:Gold / Q000737:chemistry; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D011437:Propylamines; D015203:Reproducibility of Results; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D014048:Tolonium Chloride / Q000737:chemistry; D000509:alpha-Fetoproteins / Q000737:chemistry*
chemical_list: D055910:Antibodies, Immobilized; C509968:MCM-41; D011437:Propylamines; D012821:Silanes; D000509:alpha-Fetoproteins; D014048:Tolonium Chloride; D006046:Gold; D012822:Silicon Dioxide; C477625:amino-propyl-triethoxysilane
keywords: Alpha fetoprotein; Gold nanoparticles; MCM-41; Sandwich-type electrochemical immunosensor; Toluidine blue