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.

Abstract: Reagents and assays for kinase, phosphatase and protease enzyme activity which employ metal ion-phosphate ligand specific binding and fluorescent polymer superquenching are described. The assays provide a general platform for the measurement of kinase, phosphatase and protease enzyme activity using peptide and protein substrates. Reagents and assays based on DNA hybridization and reagents and assays for proteins which employ aptamers, antibodies and other ligands are also described.

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.

Abstract: Compositions including biocidal reagents and articles treated or coated therewith are described. The compositions can be used to make passive biocidal surfaces. Exemplary biocidal reagents include visible light-absorbing polyelectrolytes which act as passive biocides upon exposure to radiation, including relatively weak “background” radiation such as natural light sources (e.g., indirect sunlight) and artificial light sources. Methods of treating or coating surfaces with the compositions are also described.

Abstract: Non-fluorescent dyes (i.e., dark quenchers) which can be used to quench the fluorescence of energy donors in bioassays through fluorescence resonance energy transfer (FRET) are described. The dark quenchers can be associated with (e.g., conjugated to) peptides, proteins, antibodies, DNA/RNA, or other biological molecules or receptors or complexed to metal containing compounds to develop bioassays based on donor-acceptor energy transfer. Bioassays are also described wherein an increase or a decrease in separation distance between a fluorescent donor compound and a dark quencher or dark quencher conjugate is detected. Kits including the dark quenchers or dark quencher conjugates are also described.

Abstract: Bioconjugates, kits and assays for detecting the activity of protease enzymes such as ?-secretase and caspase enzymes are described. The bioconjugates include a tether having a segment capable of recognizing and interacting with (e.g., being cleaved by) the enzyme, a fluorescer including a plurality of fluorescent species conjugated to a first location on the tether, and a quencher conjugated to a second location on the tether. The segment capable of recognizing and interacting with the protease enzyme (e.g., ?-secretase or caspase) is located between the first and second locations on the tether. The plurality of fluorescent species are associated with one another such that the quencher is capable of amplified super-quenching of the fluorescer. The assay is suitable for screening potential drugs for their efficiency in inhibiting the activity of protease enzymes such as ?-secretase in a high throughput format where the potential drugs are evaluated.

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 device for detecting volatile chemical reagents based on fluorescence quenching analysis that is capable of detecting neutral electron acceptor molecules. The device includes a fluorescent material, a contact region, a light source, and an optical detector. The fluorescent material includes at least one polymer-surfactant complex. The polymer-surfactant complex is formed by combining a fluorescent ionic conjugated polymer with an oppositely charged surfactant. The polymer-surfactant complex may be formed in a polar solvent and included in the fluorescent material as a solution. Alternatively, the complex may be included in the fluorescent material as a thin film. The use of a polymer-surfactant complex in the fluorescent material allows the device to detect both neutral and ionic acceptor molecules. The use of a polymer-surfactant complex film allows the device and the fluorescent material to be reusable after exposing the fluorescent material to a vacuum for limited time.

Abstract: The addition of oppositely charged surfactant to fluorescent ionic conjugated polymer forms a polymer-surfactant complex that exhibits at least one improved photophysical property. The conjugated polymer is a fluorescent ionic polymer that typically has at least one ionic side chain or moiety that interacts with the specific surfactant selected. The photophysical property improvements may include increased fluorescence quantum efficiency, wavelength-independent emission and absorption spectra, and more stable fluorescence decay kinetics. The complexation typically occurs in a solution of a polar solvent in which the polymer and surfactant are soluble, but it may also occur in a mixture of solvents. The solution is commonly prepared with a surfactant molecule:monomer repeat unit of polymer ratio ranging from about 1:100 to about 1:1. A polymer-surfactant complex precipitate is formed as the ratio approaches 1:1. This precipitate is recoverable and usable in many forms.

Abstract: A bioconjugate comprising a fluorescer (P) linked to a quencher (Q) by a tether (T) is provided. The tether (T) includes a segment that can recognize and interact with a target biomolecule. In the absence of a specific interaction of the bioconjugate with an enzyme or other target biomolecule recognizing the bioconjugate, the fluorescence of the polymer (P) is attenuated or modified by the relatively close proximity thereto of the quencher (Q). As a consequence of the association of the bioconjugate with the target biomolecule, a reaction can occur which results in a cleavage of the bioconjugate tether and a release of the fluorescent polymer and/or quencher. This sequence of events can be followed by an enhancement or amplification of the polymer fluorescence.

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.