title: Reversible surface thiol immobilization of carboxyl group containing haptens to a BIAcore biosensor chip enabling repeated usage of a single sensor surface.
abstract: We describe a reversible immobilization method for carboxyl group containing haptens that makes the repeated usage of a BIAcore biosensor chip possible. Haptens which are immobilized according to the surface thiol method can be removed completely from the sensor surface again by a reducing step. In the first part of our study, analogues of the herbicides 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid were immobilized in succession to a biosensor surface of a BIAcore surface plasmon resonance instrument according to the thiol coupling method. Direct kinetic analysis of these ligands to a polyclonal anti-2,4-dichlorophenoxyacetic acid antibody were performed using these biosensor surfaces. In the second part of the study, different amounts of 2,4-dichlorophenoxyacetic acid were sequentially immobilized onto the same biosensor surface in order to generate a calibration plot for 2,4-dichlorophenoxyacetic acid. Using this plot, the quantitative detection of the herbicide down to a concentration of 0.1 microg/mL, the maximum admissible concentration of pesticides in drinking water, is possible.
authors.affiliation: Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schlecht
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nomura
authors.forename: Till
authors.initials: T
authors.lastname: Bachmann
authors.forename: Isao
authors.initials: I
authors.lastname: Karube
mesh_terms: D015085:2,4,5-Trichlorophenoxyacetic Acid / Q000031:analogs & derivatives / Q000737:chemistry / Q000276:immunology; D015084:2,4-Dichlorophenoxyacetic Acid / Q000031:analogs & derivatives / Q000737:chemistry / Q000276:immunology; D000906:Antibodies / Q000276:immunology; D002138:Calibration; D006241:Haptens / Q000737:chemistry* / Q000276:immunology*; D006540:Herbicides / Q000737:chemistry / Q000276:immunology; D007118:Immunoassay; D007700:Kinetics; D015394:Molecular Structure; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D000906:Antibodies; D006241:Haptens; D006540:Herbicides; D013438:Sulfhydryl Compounds; D015084:2,4-Dichlorophenoxyacetic Acid; D015085:2,4,5-Trichlorophenoxyacetic Acid