title: Biofunctionalized magnetic nanoparticles for specifically detecting biomarkers of Alzheimer's disease in vitro.
abstract: Magnetic nanoparticles biofunctionalized with antibodies against β-amyloid-40 (Aβ-40) and Aβ-42, which are promising biomarkers related to Alzheimer's disease (AD), were synthesized. We characterized the size distribution, saturated magnetizations, and stability of the magnetic nanoparticles conjugated with anti-Aβ antibody. In combination with immunomagnetic reduction technology, it is demonstrated such biofunctionalized magnetic nanoparticles are able to label Aβs specifically. The ultralow-detection limits of assaying Aβs in vitro using the magnetic nanoparticles via immunomagnetic reduction are determined to a concentration of ∼10 ppt (10 pg/mL). Further, immunomagnetic reduction signals of Aβ-40 and Aβ-42 in human plasma from normal samples and AD patients were analyzed, and the results showed a significant difference between these two groups. These results show the feasibility of using magnetic nanoparticles with Aβs as reagents for assaying low-concentration Aβs through immunomagnetic reduction, and also provide a promising new method for early diagnosis of Alzheimer's disease from human blood plasma.
authors.affiliation: Institute of Electro-Optical Science and Technology, National Taiwan Normal University, Taipei 116, Taiwan.
authors.forename: Che-Chuan
authors.initials: CC
authors.lastname: Yang
authors.forename: Shieh-Yueh
authors.initials: SY
authors.lastname: Yang
authors.forename: Jen-Jie
authors.initials: JJ
authors.lastname: Chieh
authors.forename: Herng-Er
authors.initials: HE
authors.lastname: Horng
authors.forename: Chin-Yih
authors.initials: CY
authors.lastname: Hong
authors.forename: Hong-Chang
authors.initials: HC
authors.lastname: Yang
authors.forename: K H
authors.initials: KH
authors.lastname: Chen
authors.forename: B Y
authors.initials: BY
authors.lastname: Shih
authors.forename: Ta-Fu
authors.initials: TF
authors.lastname: Chen
authors.forename: Ming-Jang
authors.initials: MJ
authors.lastname: Chiu
mesh_terms: D000465:Algorithms; D000544:Alzheimer Disease / Q000378:metabolism*; D016229:Amyloid beta-Peptides / Q000032:analysis / Q000737:chemistry / Q000276:immunology; D000906:Antibodies / Q000737:chemistry / Q000276:immunology; D015415:Biomarkers; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007120:Immunochemistry; D007202:Indicators and Reagents; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D053758:Nanoparticles; D010316:Particle Size; D010446:Peptide Fragments / Q000032:analysis / Q000737:chemistry / Q000276:immunology
chemical_list: D016229:Amyloid beta-Peptides; D000906:Antibodies; D015415:Biomarkers; D007202:Indicators and Reagents; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)