title: Fabrication of micromagnetic beads with molecular recognition/electron-transfer peptides for the sensing of ovalbumin.
abstract: Electrochemical sensing of ovalbumin (OVA) was performed using magnetic beads with OVA recognition (RNRCKGTDVQAW)/electron-transfer (YYYYC) peptides. The focus of this study was to construct a highly sensitive and regenerative tool for OVA detection based on the interaction between a protein and peptide-1(RNRCKGTDVQAWYYYYC). The peptide-1 was introduced to the bead through four types of cross-linking reagents. Magnetic beads of different sizes with N-(6-maleimidocaproyloxy)sulfosuccinimide (Sulfo-EMCS) were also prepared. An oxidation peak due to tyrosine residues at 0.65 V depended on the distance of the electron-transfer peptide from the bead surface and on the surface area of the magnetic beads that contacted the electrode surface. The response of the electro-transfer peptide moiety was decreased because the protein was accumulated via the recognition peptide on the beads. When using Sulfo-EMCS and beads that were 6.0-6.9 μm in diameter, the calibration curve of OVA was linear and ranged from 8.0 × 10-13to 2.0 × 10-11M. To regenerate the magnetic beads, the measurements were achieved after removal of the OVA using a denaturing reagent. When OVA was added to fetal bovine serum containing a complex matrix, OVA was recovered at a rate of 98-100%. Consequently, these magnetic beads could be a powerful tool for the sensing of OVA in real samples.
authors.affiliation: Maebashi Institute of Technology, Gunma, 371-0816, Japan. Electronic address: kzsuga@maebashi-it.ac.jp.
authors.forename: Kazuharu
authors.initials: K
authors.lastname: Sugawara
authors.affiliation: Department of Environmental Biology and Chemistry, Graduate School of Science and Engineering for Research, University of Toyama, Toyama, 930-8555, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Kuramitz
authors.affiliation: Maebashi Institute of Technology, Gunma, 371-0816, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shinohara
mesh_terms: D055664:Electrochemical Techniques; D004566:Electrodes; D004579:Electron Transport; D004583:Electrons; D008280:Magnetics; D010047:Ovalbumin / Q000032:analysis*; D010455:Peptides / Q000737:chemistry*
chemical_list: D010455:Peptides; D010047:Ovalbumin
keywords: Electron-transfer peptide; Magnetic bead; Molecular recognition peptide; Ovalbumin