title: Glucose oxidase assisted homogeneous electrochemical receptor binding assay for drug screening.
abstract: Although the idea of homogeneous electrochemical immunoassay using antibody and an electroactive modified antigen as a probe looks to be very useful for high-throughput drug screening, there have been few reports. One reason for this is the difficulty experienced making an electroactive probe, because the introduction of electroactive compounds to antigens often interferes with the antigen-antibody interaction. To apply a homogeneous electrochemical assay to drug screening, we have designed new probes referring to the information of immobilization on beads which could identify the drug receptor. FK506 (also called Tacrolimus), immunosuppressive agent is modified with ferrocene derivatives as an electron mediator between glucose oxidase and an electrode, at a non-obstructing part. One of the probes still indicated the electrochemical activity as a mediator and had the specific binding capability for FKBP12 (FK506 binding protein). The current decrease in response to the additional FKBP12, detected with constant voltage amperometry using the probe, was observed within 5 min. Then, free FK506 as a leader drug, rapamycin and cyclosporine A as unknown drugs were used as a model for drug screening. Since the order of response currents at the same concentration of each drug reflected their binding constants, it was shown that binding capacity of an unknown drug candidate could be estimated by comparison of response currents between the leader drug and the unknown drug candidate. Thus, this glucose oxidase assisted homogeneous electrochemical drug-receptor binding assay has been proved to be a useful tool for drug screening.
authors.affiliation: Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan.
authors.forename: Hisakage
authors.initials: H
authors.lastname: Funabashi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Imamura
authors.forename: Masayasu
authors.initials: M
authors.lastname: Mie
authors.forename: Takashi
authors.initials: T
authors.lastname: Manabe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Handa
authors.forename: Masuo
authors.initials: M
authors.lastname: Aizawa
authors.forename: Eiry
authors.initials: E
authors.lastname: Kobatake
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D004353:Drug Evaluation, Preclinical / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005949:Glucose Oxidase / Q000032:analysis / Q000737:chemistry*; D007166:Immunosuppressive Agents / Q000032:analysis / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016559:Tacrolimus / Q000032:analysis* / Q000737:chemistry; D022021:Tacrolimus Binding Proteins / Q000032:analysis* / Q000737:chemistry
chemical_list: D007166:Immunosuppressive Agents; D005949:Glucose Oxidase; D022021:Tacrolimus Binding Proteins; D016559:Tacrolimus