Other

USA As Represented by Secretary of the Navy

University System of Maryland

Washington Research Foundation

The Queen's University of Belfast

Richard B Thompson

Marcia W Patchan

Badri P Maliwal

Vincent L Feliccia

Zhengfang Ge

Daniel Elbaum

David W Christianson

Carol Ann Fierke

Imre Lengyel

Paul Yager

Joseph R Lakowicz

Carl A Villarruel

Henryk Szmacinski

Alvydas J Ozinskas

Michael P Levine

Eric R Jones

Sabina Merlo

Carol A Fierke

Zhenfang Ge

Huihui Zeng

Rebecca Bozym

Hui Hui Zeng

Michele Cramer

Graham Franke

Leslie Bourne

Evgenia Matveeva

The present invention provides for the use of hydroxyapatite-selective fluorescent dyes in combination with fluorescence lifetime imaging to detect any hydroxyapatite spherules or hydroxyapatite deposits in the retina tissue of a subject, including the peripheral or macula tissue, wherein the hydroxyapatite spherules or hydroxyapatite deposits initiate or support the growth of sub-RPE deposits and correlates with age-related macular degeneration and/or Alzheimer's disease.

Methods for detecting and/or predicting age-related macular degeneration and/or Alzheimer's disease

Labels and methods are provided for detecting deposits, including drusen, sub-retinal deposits, basal laminar and linear deposits, and the like. The labels can detect the presence, progression, or regression of hydroxyapatite, which can be indicative of the presence or the potential to develop such deposits. The labels can include a conjugate comprising a hydroxyapatite binding moiety and a label moiety, which can provide a detectable signal upon binding of the conjugate to hydroxyapatite. The labels and methods can be utilized to detect deposits in eye tissue, such as the retina, brain tissue, or the like. Methods are also provided for utilizing the present labels to predict or diagnose a neurodegenerative disease, including age-related macular degeneration. Accordingly, some methods can predict or diagnose age-related macular degeneration, including early signs or advanced forms thereof, based on the presence of hydroxyapatite in a tissue sample obtained from a subject.

Methods and compositions for detecting drusen and predicting age-related macular degeneration

A method for determining metal ions, both qualitatively and quantitatively, is disclosed. The method utilizes emission from fluorescence resonance energy transfer from a luciferase-carbonic anhydrase conjugate or fusion protein to an acceptor ligand in the presence of metal ion bound to the protein to measure free metal ion concentrations down to picomolar concentration ranges. The method is relatively insensitive to contaminants, and so can be used to measure metal ion concentrations in cells, body fluids or environmental samples without extensive sample preparation.

Bioluminescent metal ion assay

Provided are sensor devices, methods, systems, and kits for measuring the concentration of at least one target analyte. Sensor devices may be mounted into an optical system for measuring the target analyte. Example sensor devices may also be removably mounted in a holder that enables the sensor device to be inserted into a container that allows the sensor device to contact an analyte containing sample. Further provided are methods that include contacting a sensor device with an analyte-containing sample; determining analyte concentration; and optionally repeating these steps to determine if the analyte concentration spikes or exceeds a predetermined level, which may trigger an alarm response.

Analyte sensor devices and holders, and methods and systems utilizing the same

The invention relates to compositions and kits for homogeneous fluorescence polarization (anisotropy) assays for detecting and quantifying metal ions in solution. Metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule effects a measurable change in anisotropy as will the binding of metal ions to a fluorescent labeled macromolecule. Binding of the fluorescent ligand to the unlabeled macromolecule is metal dependent with the change in anisotropy being proportional to the concentration of bound metal ions. Conversely, if the fluorescent label is first conjugated to a macromolecule and the macromolecule is subsequently stripped of metal ion, it may then be used to signal binding of metal ions. The covalently bound fluorescent label exhibits changes in anisotropy proportional to the concentration of bound metal ions. Kits comprise a fluorescent molecule and a macromolecule.

Determination of metal ions in solution by photoluminescence anisotropy

A highly selective and sensitive of a carbonic anhydrase-based method for measurement of zinc ion by an excitation ratiometric format based on resonance energy transfer: i.e., where the zinc ion level is transduced as the ratio of fluorescence intensities excited at two different excitation wavelengths, is provided. The method can be used very well in a fluorescence microscopy format. A detection limit of about 10 pM in zinc buffered systems, a ten to one thousand-fold improvement on the Fura indicators (which respond to Ca and Mg as well), and a one hundred thousand-fold improvement on the recently described FuraZin-1 is achieved.

Excitation ratiometric fluoroscent biosensor for zinc ion at picomolar levels

Homogeneous fluorescence polarization (anisotropy) assays for detecting and quantifying metal ions in solution, based the metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule, or the binding of a metal ion to a fluorescent labeled macromolecule. The metal-dependent binding of a fluorescent ligand to an unlabeled macromolecule (metallo-macromolecule) effects a measurable change in anisotropy as will the binding of metal ions to a fluorescent labeled macromolecule. Binding of the fluorescent ligand to the unlabeled macromolecule is metal dependent with the change in anisotropy being proportional to the concentration of bound metal ions. No binding of the fluorescent ligand to the macromolecule occurs in the absence of metal ions. Conversely, if the fluorescent label is first conjugated to a metallo-macromolecule and the metallo-macromolecule is subsequently stripped of its metal ion, it may then be used to transduce the binding of metal ions. Transduction is provided wherein the covalently bound fluorescent label exhibits changes in anisotropy proportional to the concentration of bound metal ions. In all methods, the change in anisotropy may be simply related to the metal ion concentration of the test solution.

This invention generally relates to the detection, determination, and quantitation of certain ions and small molecules involving the quenching of a fluorescent label attached to a macromolecule, often due to fluorescence energy transfer to a colored inhibitor or certain metal ions bound to the macromolecule.

Enzyme-based fluorescence biosensor for chemical analysis

The invention described in detail herein relates to the detection, determination, and quantitation of certain ions and small molecules in solution. The invention specifically relates to improvements in the area of photoluminescent sensors for use in a detection scheme involving the alteration of a photoluminescent label or moiety attached to or associated with an analyte binding macromolecule. One may use the changes in photoluminescence lifetime, changes in ratios of photoluminescence intensity or changes in photoluminescence polarization (anisotropy) to determine the analyte. The photoluminescence change measured correlates to the concentration of the ion or molecule in solution.

Photoluminescent sensors of chemical analytes

A fluorometric luminescence immunoassay method includes forming a sample by exposing a first immune reaction reactant to a second immune reaction reactant capable of reacting with the first reactant, one of the first and second immune reaction reactants being labelled with a photoluminescent energy transfer donor and the other being labelled with a photoluminescent energy transfer acceptor complementary to the photoluminescent donor. At least the photoluminescent donor has the property of photoluminescence, and the photoluminescent donor and acceptor are chosen so that when the first immune reaction reactant reacts with the second immune reaction reactant, the donor and the acceptor are capable of interacting to produce a detectable luminescence lifetime change. The sample is excited with radiation, and the resulting emission is detected. The apparent luminescent lifetime is then calculated to determine the presence of a reaction product of the first and second immune reaction reactants.

Fluorescent energy transfer immunoassay

The present invention is a process and apparatus for metal ion detection. The process of the invention has the steps of (1) disposing, in an analyte medium, a macromolecule suitable for selective complexation with the target metal ion species; (2) disposing, in the analyte medium, an appropriate photoluminescent indicator that will emit in a measurably different manner when bound to the metallomacromolecule complex, compared with its unbound state; (3) exciting the photoluminescent indicator species; and (4) monitoring the emission of the photoluminescent indicator species to detect changes in its emission. The apparatus of the invention has (1) a macromolecule suitable for selective complexation with the target metal ion species disposed in an analyte medium; (2) an appropriate photoluminescent indicator that will emit in a measurably different manner when bound to the metallomacromolecule complex, compared with its unbound state, also disposed in the analyte medium; (3) a source for exciting the photoluminescent indicator species; and (4) a detector for monitoring the emission of the photoluminescent indicator species to detect changes in its emission.

Selective metal ion detection using a photoluminescent indicator binding

The invention is directed to a light producing microemulsion formed in the resence of a surfactant/cosurfactant pair from an oil phase medium having at least an oxalate derivative and a fluorescer compound dissolved in it and an aqueous phase medium containing at least an oxidant dissolved in it. The light produced in such a microemulsion can be used to analyze aqueous oxidant-containing samples by comparing the amount of light produced by a microemulsion formed from a known quantity of an oxidant to a similar sample containing an unknown quantity of an oxidant. The comparison can be made by any well known photosensitive means and can be computerized.

Chemiluminescent microemulsions

Method of detecting oxidizing agents in aqueous media through the use of

A photoluminescence sensor for detecting a photoluminescent light from a toluminescent material is disclosed. In a preferred embodiment the photoluminescence sensor comprises: a source of light; a concave mirror having at least one perforation for passing the source light through the at least one perforation; an optical waveguide having proximal and distal ends with the photoluminescent material being disposed at the distal end; an objective for directing the source light into the proximal end of the waveguide; an objective for receiving photoluminescent light and for focusing the photoluminescent light onto the perforated concave mirror; a liquid filter for passing the photoluminescent light reflected from the perforated concave mirror to a detector to detect the photoluminescent light. The sensor can also include a chopper disposed at the output end of the objective for modulating the light source at a select frequency and a lock-in amplifier tuned to measure the output from the detector at the select frequency.

Growing community of inventors

Baltimore, MD, United States of America

Richard B Thompson