title: Ceria Doped Zinc Oxide Nanoflowers Enhanced Luminol-Based Electrochemiluminescence Immunosensor for Amyloid-β Detection.
abstract: In this work, ceria doped ZnO nanomaterials with flower-structure (Ce:ZONFs) were prepared to construct a luminol-based electrochemiluminescence (ECL) immunosensor for amyloid-β protein (Aβ) detection. Herein, carboxyl groups (-COOH) covered Ce:ZONFs were synthesized by a green method with lysine as reductant. After that, Ce:ZONFs-based ECL nanocomposite was prepared by combining the luminophore of luminol and Ce:ZONFs via amidation and physical absorption. Luminol modified on Ce:ZONFs surface could generate a strong ECL signal under the assistance of reactive oxygen species (ROSs) (such as OH(•) and O2(•-)), which were produced by a catalytic reaction between Ce:ZONFs and H2O2. It was worth noticing that a quick Ce(4+) ↔ Ce(3+) reaction in this doped material could increase the rate of electron transfer to realize the signal amplification. Subsequently, the luminol functionalized Ce:ZONFs (Ce:ZONFs-Lum) were covered by secondary antibody (Ab2) and glucose oxidase (GOD), respectively, to construct a novel Ab2 bioconjugate (Ab2-GOD@Ce:ZONFs-Lum). The wire-structured silver-cysteine complex (AgCys NWs) with a large number of -COOH, which was synthesized by AgNO3 and l-cysteine, was used as substrate of the immunosensor to capture the primary antibody (Ab1). Under the optimal conditions, this proposed ECL immunosensor had exhibited high sensitivity for Aβ detection with a wide linear range from 80 fg/mL to 100 ng/mL and an ultralow detection limit of 52 fg/mL. Meanwhile, this biosensor had good specificity for Aβ, indicating that the provided strategy had a promising potential in the detection of Aβ.
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Jing-Xi
authors.initials: JX
authors.lastname: Wang
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhuo
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Wang
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Ruo
authors.initials: R
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Luminescent and Real-Time Analytical Chemistry, Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University , Chongqing 400715, PR China.
authors.forename: Ya-Qin
authors.initials: YQ
authors.lastname: Chai
mesh_terms: D016229:Amyloid beta-Peptides / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D002563:Cerium / Q000737:chemistry; D055664:Electrochemical Techniques; D005949:Glucose Oxidase / Q000378:metabolism; D007118:Immunoassay / Q000379:methods*; D008163:Luminescent Measurements; D008165:Luminol / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D016229:Amyloid beta-Peptides; D002563:Cerium; D008165:Luminol; D005949:Glucose Oxidase; D015034:Zinc Oxide
keywords: amyloid-β; ceria doped zinc oxide nanoflowers; electrochemiluminescence; immunosensor; luminol