title: Evaluation of a high-affinity QCM immunosensor using antibody fragmentation and 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer.
abstract: This study evaluated construction of a highly affinitive quartz crystal microbalance (QCM) immunosensor using anti-C-reactive protein (CRP) antibody and its fragments for CRP detection. Three types of antibody were immobilized on the surface of a QCM via covalent-bounding. Then affinity was evaluated through antigen-antibody binding between CRP and its antibody. Affinity between antigen-antibody was shown to be highest when anti-CRP F(ab')2-IgG antibody (70 microg/mL) was immobilized on the QCM. In case of anti-CRP F(ab')2-IgG antibody, affinity which was attributable to antigen-antibody binding was almost twice that of anti-CRP IgG antibody, which is used conventionally for QCM immunosensors. In addition, when it was treated with 2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate, so-called MPC polymer, highly affinitive and selective immunosensing for CRP was achieved without non-specific binding from plasma proteins in human serum. When anti-CRP F(ab')2-IgG antibody was immobilized on the QCM, the detection limit and the linearity of CRP calibration curve were achieved at concentrations from 0.001 to 100 microg/dL even during investigation in serum samples. Experimental results verified the successful construction of a highly affinitive and selective QCM-immunosensor which was modified with anti-CRP F(ab')2-IgG antibody and MPC polymer.
authors.affiliation: National Institute of Advanced Industrial Science and Technology (AIST), 1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan. shigeru-kurosawa@aist.go.jp
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kurosawa
authors.forename: Miki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Park
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Aizawa
authors.forename: Kazunori
authors.initials: K
authors.lastname: Yamada
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Hirata
mesh_terms: D000936:Antigen-Antibody Complex / Q000032:analysis; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D002097:C-Reactive Protein / Q000032:analysis* / Q000276:immunology; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D007128:Immunoglobulin Fragments / Q000032:analysis / Q000737:chemistry / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D008689:Methacrylates / Q000737:chemistry*; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000737:chemistry*
chemical_list: D000936:Antigen-Antibody Complex; D020099:Coated Materials, Biocompatible; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D008689:Methacrylates; D010767:Phosphorylcholine; C070638:2-methacryloyloxyethyl phosphorylcholine; D002097:C-Reactive Protein