title: Novel fluorescence based receptor binding assay method for receptors lacking ligand conjugates with preserved affinity: study on estrogen receptor alpha.
abstract: In this study a novel general approach is presented that allows for a straightforward design of receptor binding assays. This principle of a receptor binding assay is applied to the estrogen receptor, which is important in the management of breast cancer and for the estimation of the estrogenic potency of chemicals in the environment. The inhibitory concentrations to reduce cell proliferation in 50% of controls for 17-beta-estradiol, 4-hydroxy tamoxifen, and tamoxifen are determined to be 61 nM, 33 nM, and 17 microM, respectively. The measurement time of the nanoparticle based immunoassay format is 3 s. The Z' factor, which is calculated to be 0.89, reflects the excellent assay performance.
authors.affiliation: EVOTEC Technologies GmBH, Merowingerplatz 1a, 40225 Düsseldorf, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Christoph
authors.forename: Franz-Josef
authors.initials: FJ
authors.lastname: Meyer-Almes
mesh_terms: D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D047628:Estrogen Receptor alpha; D007118:Immunoassay / Q000379:methods; D020128:Inhibitory Concentration 50; D008024:Ligands; D015394:Molecular Structure; D011485:Protein Binding; D011960:Receptors, Estrogen / Q000378:metabolism*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013629:Tamoxifen / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D047628:Estrogen Receptor alpha; D008024:Ligands; D011960:Receptors, Estrogen; D013629:Tamoxifen; C016601:afimoxifene; D004958:Estradiol