Abstract: Complexes of a biotinylated fluorescent polymer and a biotin binding protein and solid supports coated with the fluorescent polymer complexes are described. The complexes can be used as sensors for detecting biological recognition events (e.g., nucleic acid hybridization reactions or enzymatic induced polypeptide cleavage). Methods of making the complexes and methods of using the complexes for detecting the presence and/or amount of a target analyte in a sample are also described. The target analyte can be an enzyme (e.g., &bgr;-secretase) or a nucleic acid (e.g., a single stranded or double stranded nucleic acid).

Abstract: A chemical composition including a fluorescent polymer and a receptor that is specific for both a target biological agent and a chemical moiety including (a) a recognition element, (b) a tethering element, and (c) a property-altering element is disclosed. Both the fluorescent polymer and the receptor are co-located on a support. When the chemical moiety is bound to the receptor, the property-altering element is sufficiently close to the fluorescent polymer to alter the fluorescence emitted by the polymer. When an analyte sample is introduced, the target biological agent, if present, binds to the receptor, thereby displacing the chemical moiety from the receptor, resulting in an increase of detected fluorescence. Assays for detecting the presence of a target biological agent are also disclosed.