title: Direct immobilization of gold-binding antibody fragments for immunosensor applications.
abstract: A novel method that enables antibody fragments to be immobilized on a sensor substrate with a high binding capability using molecular recognition has been developed. Using genetic engineering, we fabricated bispecific recombinant antibody fragments, which consist of two kinds of antibody fragments: a gold antibody fragment and a target molecule antibody fragment. Surface plasmon resonance (SPR) analysis indicated that these gold-binding bispecific antibody fragments bind directly to the gold substrate with high affinity (K(D) approximately 10(-9) M). About 70% of the bispecific antibody fragments immobilized on the gold substrate retained their target protein-binding efficiency. The Sips isotherm was used to assess the heterogeneity in antibody affinity for the bispecific antibody fragments. The results showed that the immobilized bispecific antibody fragments exhibited an increased homogeneity of affinity (K(D)) to target molecules when compared with monospecific antibody fragments immobilized by conventional methods. The use of bispecific antibody fragments to directly immobilize antibody fragments on a solid-phase substrate offers a useful platform for immunosensor applications.
authors.affiliation: Corporate R&D Headquarters, Frontier Research Center, Canon Inc., 30-2, Shimomaruko 3-chome, Ohta-ku, Tokyo 146-8501, Japan. ibii.takahisa@canon.co.jp
authors.forename: Takahisa
authors.initials: T
authors.lastname: Ibii
authors.forename: Masaru
authors.initials: M
authors.lastname: Kaieda
authors.forename: Satoru
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: Hidenori
authors.initials: H
authors.lastname: Shiotsuka
authors.forename: Hideki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Umetsu
authors.forename: Izumi
authors.initials: I
authors.lastname: Kumagai
authors.forename: Takeshi
authors.initials: T
authors.lastname: Imamura
mesh_terms: D018033:Antibodies, Bispecific / Q000276:immunology; D055910:Antibodies, Immobilized / Q000276:immunology*; D000915:Antibody Affinity; D015374:Biosensing Techniques / Q000379:methods*; D006046:Gold / Q000737:chemistry*; D007128:Immunoglobulin Fragments / Q000737:chemistry*; D007136:Immunoglobulins / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods
chemical_list: D018033:Antibodies, Bispecific; D055910:Antibodies, Immobilized; D007128:Immunoglobulin Fragments; D007136:Immunoglobulins; D006046:Gold