| abstract |
The invention provides new compositions and methods for qualitative and quantitative immunoassay employing cyclodextrin (CD), labels. The labels comprise a CD ''host'' molecule that includes a fluorescent or chemiluminescent ''guest'' molecule, with a ''coupling group'' available on the CD. The labels are used for labeling various substances such as ligands, antigens, and antibodies, to provided tracers for use in immunoassays and other ligand binding assays. Methods are disclosed for competitive, and noncompetitive ''sandwich'' type assays, as well as heterogeneous and homogeneous assays. The invention provides the following properties and advantages: 1) safer, nonradioactive tracers; 2) potentially higher signal efficiency and longer shelf life; 3) coupling groups for one-step labeling; 4) chemiluminescent detection for more sensitivity; 5) multiple CD labels for efficient labeling; 6) chemical/physical similarity for easier synthesis and use; 7) different colored labels with similar properties; 8) methods are readily automated for high volume applications. The invention also provides catalytic CD labels and methods. |