title: Combined method of immunoaffinity membrane within tubes and MALDI-TOF MS for capturing and analyzing amyloid beta.
abstract: Amyloid beta 1-40 peptide was specifically isolated and analyzed from human plasma spiked with amyloid beta using a combined method of biotinylated anti-amyloid beta antibody binding to membrane-immobilized avidin (immunoaffinity membrane) and matrix-assisted laser desorption /ionization time-of-flight mass spectrometry (MALDI-TOF MS). A solution of 10 μL containing 13.6 ng to 2.9 μg of amyloid beta peptide was examined in this method. After the isolated amyloid beta peptide from the spiked human plasma containing 2.9 μg of amyloid beta peptide was incubated in the presence of trifluoroacetic acid, fibrillization of the peptides was observed using a thioflavin T assay. Furthermore, an immunoaffinity membrane present on the inner wall of a tube (diameter 2 mm) captured the amyloid beta peptide from the spiked human plasma. Our results indicate that the combination of the immunoaffinity membrane procedure and MALDI-TOF MS can be used to capture and analyze the target antigens such as amyloid beta in micro-spaces.
authors.affiliation: Department of Chemistry and Biology, Graduate School of Science and Engineering (Science), Ehime University, Matsuyama City, 790-8577, Japan. shimazaki.yoji.my@ehime-u.ac.jp.
authors.forename: Youji
authors.initials: Y
authors.lastname: Shimazaki
authors.affiliation: Faculty of Science, Ehime University, Matsuyama, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Takatsu
mesh_terms: D016229:Amyloid beta-Peptides / Q000032:analysis* / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D055910:Antibodies, Immobilized / Q000737:chemistry / Q000276:immunology; D001360:Avidin / Q000737:chemistry; D002846:Chromatography, Affinity / Q000379:methods*; D006801:Humans; D008567:Membranes, Artificial; D010446:Peptide Fragments / Q000032:analysis* / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D055503:Protein Multimerization; D017433:Protein Structure, Secondary; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D016229:Amyloid beta-Peptides; D055910:Antibodies, Immobilized; D008567:Membranes, Artificial; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); D001360:Avidin
keywords: Amyloid beta; MALDI-TOF MS; Micro-space; Thioflavin T assay