Abstract: Quaternary nitrogen heterocyclic boronic acid-containing compounds are described, which are sensitive to glucose and fructose, as well as a variety of other physiologically important analytes, such as aqueous chloride and iodide, and a method of using the compounds. Also disclosed is a contact lens doped with the quaternary nitrogen heterocyclic boronic acid-containing compound, and a method of using the doped contact lens to measure the concentration of analyte in tears under physiological conditions.

Abstract: A method for enhancing fluorescence of a biomolecule includes the step of associating the biomolecule having intrinsic fluorescence with a sensing surface that contains nanostructured metal. Association of the biomolecule with the nanostructured metal enhances its intrinsic fluorescence, which is detected upon exposure to electromagnetic radiation of a suitable wavelength. The sensing surface may include capture or ligand molecule which binds to the biomolecule and sequesters it in proximity to the nanostructured metal, thereby causing its fluorescent signal to be enhanced. The method can be used in label-free bioassays for detection of interacting biomolecules, such as antibody-antigen binding.

Abstract: The spectroscopic and photophysical properties of fluorescent probes comprising donor-acceptor derivatives comprising the boric acid group or a derivative of boric acid, B(OH)3 (or borate ion, BO(OH)2?1), arsenious acid, H3 AsO3 (or arsenite ion, H2AsO3?1), telluric acid, H6TeO6 (or tellurate ion, H5 TeO6?1) or germanic acid, Ge(OH)6 (or germanate ion, GeO(OH)3?1) are described. Method of using said probes are also provided.

Abstract: A method and kit for determining the quantity of an analyte include providing a functionalized substrate and a reagent. The functionalized substrate includes metallic nanoparticles and a plurality of substantively identical bioactive target molecules affixed to a substrate. The bioactive target molecule binds to a particular analyte. The reagent includes identical detection molecules. Each detection molecule includes a fluorophore, and binds to a particular analyte or competes with a particular analyte for binding to the target molecule. The functionalized substrate is contacted to a test sample and the reagent. The functionalized substrate and a covering solution are exposed to polarized electromagnetic waves that excite the fluorophore. A quantity of the particular analyte in the test sample is determined based on measuring polarization anisotropy of fluorescent emissions from the substrate and the covering solution.

Abstract: A new approach is described to making luminophores which display long emission wavelengths, long decay times, and high quantum yields. These luminophores are covalently linked or otherwise closely associated pairs with a long lifetime resonance energy transfer (RET) donor e.g., a ruthenium (Ru) metal-ligand complex, and a long wavelength acceptor, e.g., Texas Red. The donor and acceptor can be covalently linked by, e.g., poly-proline spacers. The long lifetime donor results in a long lived component in the acceptor decay which is due to RET. The quantum yield of the luminophores approaches that of the higher quantum yield acceptor, rather than the lower quantum yield typical of metal-ligand complexes. The emission maxima and decay time of such tandem luminophores can be readily adjusted by selection of the donor, acceptor and distance between them. Luminophores with these useful spectral properties can also be donor-acceptor pairs brought into close proximity by some biochemical association reaction.

Abstract: Provided herein are methods for imaging subwavelength structures in three dimensions and with high resolution. The methods comprise illuminating subwavelength structures with an illuminating wavelength of light and detecting the self-image generated thereby at a distance distal to the structures. Also provided is a method for confining propagating light to a sub-diffraction limit dimension by illuminating a surface of a metal structure with subwavelength features with a wavelength of coherent light such that light propagating from the features is confined to a dimension that is a sub-diffraction limit thereof.

Abstract: Described is a new approach to fluorescence sensing based on a mixture of fluorophores, one of which is sensitive to the desired analyte. If a long lifetime analyte-insensitive fluorophore is mixed with a short lifetime analyte-sensitive fluorophore, the modulation of the emission at conveniently low frequencies becomes equal to the fractional fluorescence intensity of the sensing fluorophore. Under these conditions the modulation can be used to determine the analyte concentration. This can be used with any fluorophore which changes intensity in response to analyte, and does not require the sensing fluorophore to display a change in lifetime. The feasibility of modulation-based sensing was demonstrated using mixtures of 6-carboxyfluorescein and [Ru2,2′(bipyridyl)3]2+ as a pH sensor and of the calcium probe Fluo-3 and [Ru2,2′(bipyridyl)3]2+ as a calcium sensor.

Abstract: The spectroscopic and photophysical properties of fluorescent probes comprising donor-acceptor derivatives comprising the boric acid group or a derivative of boric acid, B(OH)3 (or borate ion, BO(OH)2−1), arsenious acid, H3 AsO3 (or arsenite ion, H2AsO3−1), telluric acid, H6TeO6 (or tellurate ion, H5 TeO6−1) or germanic acid, Ge(OH)6 (or germanate ion, GeO(OH)3−1) are described. Method of using said probes are also provided.

Abstract: The present invention relates to a transition metal-ligand complex that shows changes in its luminescence lifetime characteristic and/or luminescence intensity as a function of the polarity and/or hydrogen bonding properties of its environment, and a sensor, probe, system and method based on the complex for detecting the presence, amount or concentration of a polar solvent in a medium.

Abstract: A new approach is described to making luminophores which display long emission wavelengths, long decay times, and high quantum yields. These luminophores are covalently linked or otherwise closely associated pairs with a long lifetime resonance energy transfer (RET) donor e.g., a ruthenium (Ru) metal-ligand complex, and a long wavelength acceptor, e.g., Texas Red. The donor and acceptor can be covalently linked by, e.g., poly-proline spacers. The long lifetime donor results in a long lived component in the acceptor decay which is due to RET. The quantum yield of the luminophores approaches that of the higher quantum yield acceptor, rather than the lower quantum yield typical of metal-ligand complexes. The emission maxima and decay time of such tandem luminophores can be readily adjusted by selection of the donor, acceptor and distance between them. Luminophores with these useful spectral properties can also be donor-acceptor pairs brought into close proximity by some biochemical association reaction.

Abstract: Methods and compositions for the detection and monitoring of drug therapy are provided. In particular, efficient and sensitive methods for the detection of drug ingestion are provided for determining whether individuals are complying with prescribed therapeutic regimens, and for providing a mechanism for identifying drug-resistant strains of infectious agents. The claimed methods and compositions involve the application of transdermal devices containing detection mechanisms for receiving and recording signals generated by the ingestion of a labeled drug. Such devices are attached to the skin for the duration of drug therapy and compliance is determined either by direct reading, or by remote monitoring whereby signals are transmitted from the device and received at an external site such as a healthcare facility.

Abstract: An apparatus and a method for detecting or measuring the presence of a compound capable of fluorescing in a sample. The Apparatus may contain a metal particle and a compound capable of fluorescing separated by at least one film spacer layer. The thickness of the film enhances the fluorescence of said compound due to the distance of the compound from the metal particle. The method includes spacing the compound at a distance from a metal particle, which provides an enhanced fluorescence intensity of the compound, exposing the compound to radiation and detecting the fluorescent emission. The Apparatus may also be in the form of multiple metal particles in a porous three dimensional matrix. The method also includes flowing the compound through a porous three dimensional matrix comprising multiple metal particles.

Abstract: The steady state and time resolved luminescence spectral properties of two types of novel CdS nanoparticles and nanoparticles are described. CdS nanoparticles formed in the presence of an amine-terminated dendrimer show blue emission. The emission wavelength of these nanoparticles depended on the excitation wavelength. The CdS/dendrimer nanoparticles display polarized emission with the anisotropy rising progressively from 340 to 420 nm excitation, reaching a maximal anisotropy value in excess of 0.3. A new constant positive polarized emission from luminescent nanoparticles is also described. Polyphosphate-stabilized CdS nanoparticles are described that display a longer wavelength red emission maximum than bulk CdS and display a zero anisotropy for all excitation wavelengths. Both nanoparticles display strongly heterogeneous intensity decays with mean decay times of 93 ns and 10 &mgr;s for the blue and red emitting particles, respectively.

Abstract: Compositions and methods for increasing the fluorescence intensity of molecules are provided. In particular, compositions and methods directed to increasing the intrinsic fluorescence of biomolecules and low quantum yield fluorophores are described. The intrinsic fluorescence of biomolecules is increased by positioning a metal particle and a biomolecule at a distance apart sufficient to increase the radiative decay rate of the biomolecule. Methods for the identification of nucleic acids are also provided. The compositions and methods can also be used to increase the emission of any fluorophore, such as the extrinsic probes used to label biomolecules.

Abstract: A system and method of optically measuring Na+ and K+ in a sample such as blood which contains high concentrations Na+ (up to 160 mM) and K+ (up to 6.5 mM) using a photoluminescent probe having intrinsic analyte-induced lifetime changes. Specifically, the use of lifetime-based sensing of Na+ and K+ at the extracellular concentrations present in whole blood or, blood serum. The preferred embodiment uses phase-modulation fluorometry.

Abstract: A method for determining a base sequence of a nucleotide strand in a sample utilizes a probe including a fluorescent metal-ligand complex coupled to a first oligonucleotide having a sequence complementary to the first fragment of the strand. The first mixture is exposed to an exciting amount of radiation, and the fluorescence of the metal-ligand complex is detected. The first base sequence of the first fragment is identified based on fluorescence of the metal ligand complex. A second probe differing from the first by at least one base is provided. A second base of the second fragment is identified based on the fluorescence of the metal-ligand complex of the second probe. The second base sequence is compared to the first base sequence to identify a difference between the first and second sequences to determine a base sequence of the nucleotide strand.

Abstract: The present invention relates to the determination of the presence or concentration of an analyte in a sample by visual or electronic element, using polarization based sensing techniques (14) employing fluorescent sensing (11) and reference molecules (10).

Abstract: In accordance with the present invention, a method of measuring an analyte in a sample includes the following steps. A metal-ligand complex probe is contacted with a sample containing analyte. The probe is bound to analyte in the sample to form an analyte-bound probe species. Both bound and unbound species of the probe exist in the sample. At least one of the bound and unbound species is fluorescent, with each of the bound and unbound species being optically distinguishable. The sample containing the bound and unbound species is excited with radiation, so as to produce a resulting emission from at least one of the bound and unbound species. The resulting emission is detected, so as to provide an optical measurement of the emission. Concentration of analyte in the sample is determined utilizing the optical measurement of the emission.

Abstract: The oxygen concentration of a sample is determined utilizing a water-soluble metal ligand complex which is brought into interactive proximity with the sample to form a mixture. The mixture is irradiated with electromagnetic light energy so as to cause emission of light indicative of oxygen. The emitted light is measured, and the measurement utilized so as to determine oxygen concentration of the sample.

Abstract: In accordance with the present invention, a method of conducting an assay of a sample containing an analyte of interest includes the step of forming a mixture so as to bring a metal-ligand complex into interactive proximity with the sample containing the analyte of interest. The mixture is irradiated with electromagnetic light energy so as to cause emission of light indicative of the analyte of interest. The emitted light is measured, and the measurement of the emitted light is utilized to measure the analyte of interest. The metal-ligand complex can be [Re(bcp)(CO)3(4-COOHPy)]+, [Os(phen)2(aphen)]2+, [Os(tpy)(triphos)]2+, [Os(tppz)2]2+, and [Os(ttpy)2]2+, or the like. Also, the present invention is directed to a metal-ligand complex of the formula [Re(bcp)(CO)3(4-COOHPy)]+.