Patents by Inventor Joseph R. Lakowicz

Joseph R. Lakowicz has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6200752
    Abstract: A method for detecting the presence of a nucleic acid sequence in a sample includes the step of coupling a fluorescent metal-ligand complex to an oligonucleotide having a sequence complementary to the nucleic acid sequence to form a probe. The probe is added to a sample that contains the nucleic acid sequence to form a mixture containing a reaction product. The mixture is exposed to an exciting amount of radiation. The fluorescence of the metal-ligand complex is detected, and the presence of the nucleic acid sequence is determined based on the fluorescence of the metal-ligand complex. A composition for detecting the presence of a nucleic acid sequence, includes a fluorescent metal-ligand complex coupled to an oligonucleotide having a sequence complementary to the nucleic acid sequence. A diagnostic kit for detecting the presence of a nucleic acid sequence, includes a fluorescent metal-ligand complex coupled to an oligonucleotide having a sequence complementary to the nucleic acid sequence.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: March 13, 2001
    Inventor: Joseph R. Lakowicz
  • Patent number: 6197534
    Abstract: Disclosed are methods and sensors for detecting the presence or concentration of an analyte in a sample, preferably a sugar such as glucose, which preferably utilizes a labeled engineered protein, or fragment thereof, that is capable of binding the analyte to be detected.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: March 6, 2001
    Inventors: Joseph R. Lakowicz, Leah Tolosa, Lisa Eichhorn, Govind Rao
  • Patent number: 5759767
    Abstract: A method of measuring an analyte present in animal (e.g., human) tissue or fluids such as blood or plasma. The analyte is multi-photon excitable (e.g., two-photon excitable) at a first wavelength at which the animal tissue is substantially non-absorbing. The analyte fluoresces at a second wavelength upon being excited at the first wavelength. The animal tissue is irradiated with radiation at the first wavelength so as to excite the analyte through absorption by the analyte of two or more photons of the radiation at the first wavelength. Excitation of the analyte results in a fluorescent emission from the analyte of radiation at the second wavelength. The emission at the second wavelength is detected, and the concentration of analyte determined based on the detected emission.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: June 2, 1998
    Assignee: Joseph R. Lakowicz
    Inventors: Joseph R. Lakowicz, Thomas G. Burke, Ignacy Gryczynski, Henryk Malak
  • Patent number: 5660991
    Abstract: A method of conducting an immunoassay of a sample of interest is described, including the steps of (A) coupling a luminescent asymmetric metal-ligand complex to the sample of interest to form a coupled sample, (B) exciting the coupled sample with linearly polarized electromagnetic energy to cause the coupled sample to emit fluorescent light; and (C) measuring the polarization of the fluorescent emission as a measure of a biological characteristic of the sample of interest.
    Type: Grant
    Filed: October 28, 1994
    Date of Patent: August 26, 1997
    Inventors: Joseph R. Lakowicz, Henryk Szmacinski, Ewald Terpetschnig
  • Patent number: 5648269
    Abstract: A method for determining pH or pCO.sub.2 using luminescent lifetimes and energy transfer in which an energy transfer donor-acceptor pair is exposed to a sample to be analyzed, the donor of the donor-acceptor pair being photoluminescent and the acceptor of the donor-acceptor pair being sensitive to the pH or pCO.sub.2 of the sample. One or both of the donor-acceptor pair may be bound to a carrier. The sample is irradiated and the resultant emission detected. By measuring the apparent luminescent lifetime, the pH or pCO.sub.2 of the sample can be determined.
    Type: Grant
    Filed: March 14, 1995
    Date of Patent: July 15, 1997
    Assignee: Joseph R. Lakowicz
    Inventors: Joseph R. Lakowicz, Henry K. Szmacinski
  • Patent number: 5631169
    Abstract: 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.
    Type: Grant
    Filed: January 19, 1994
    Date of Patent: May 20, 1997
    Assignees: Joseph R. Lakowicz, Richard Thompson
    Inventors: Joseph R. Lakowicz, Badri P. Maliwal, Richard Thompson, Alvydas Ozinskas
  • Patent number: 5628310
    Abstract: An apparatus and method to enable minimally invasive transdermal measurements of the fluorescence lifetime of an implanted element without reagent consumption and not requiring painful blood sampling. The monitoring apparatus displays the quantity of a selected substance present in the skin and stores the data in memory. The stored information can be transmitted via modem, or antenna, to a master station for diagnostic purposes or clinical evaluation. The use of this method and apparatus improves control of blood monitoring, and therefore, enhances long-term disease management with fewer complications.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: May 13, 1997
    Assignee: Joseph R. Lakowicz
    Inventors: Govind Rao, Henryk Szmacinski, Joseph R. Lakowicz
  • Patent number: 5624847
    Abstract: A system and method in which a photoluminescent ligand is added to a sample to be analyzed in the form of a photoluminescent probe having intrinsic analyte-induced lifetime changes. The method preferably employs phase-modulation fluorometry to measure the lifetime changes. Specific probes are disclosed for measuring various analytes, particularly ionic solutes, including H.sup.+, Ca.sup.2+ and K.sup.+.
    Type: Grant
    Filed: August 6, 1993
    Date of Patent: April 29, 1997
    Assignee: Joseph R. Lakowicz
    Inventors: Joseph R. Lakowicz, Henryk Szmacinski
  • Patent number: 5504337
    Abstract: A method and apparatus for identifying individual particles or cells which have been labeled with different fluorochromes, on the basis of the lifetime of their fluorescence, or based on different decay times for a fluorochrome in different cells.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: April 2, 1996
    Assignee: Joseph R. Lakowicz
    Inventors: Joseph R. Lakowicz, Klaus W. Berndt, Robert A. Hoffman, Bertram G. Pinsky
  • Patent number: 5485530
    Abstract: A method and apparatus for detection and/or measurement of physical characteristics of a sample based on multi-dimensional phase-modulation fluorescence lifetime imaging using at least one fluorescent probe having known and/or variable fluorescent lifetimes.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: January 16, 1996
    Assignee: Joseph R. Lakowicz
    Inventors: Joseph R. Lakowicz, Klaus W. Berndt, Kazimierz Nowaczyk, Henryk Szmacinski, Michael L. Johnson
  • Patent number: 5409835
    Abstract: Fluorescent, calcium-binding probe compounds having visible-light excitation and emission wavelengths, and a method of usage for these probe compounds in making wavelength-ratiometric or intensity-ratiometric measurements of calcium ion concentration in samples. The probe compounds generally relate to a heterocyclic part as bonded to a Ca.sup.2+ binding unit, namely, BAPTA, via an ethylenically unsaturated group; preferred examples of the heterocyclic group include benzothiazole, naphthothiazole, thiaflavin, indolenine, chloroindolenine, methoxybenzothiazole, and methoxyindolenine.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: April 25, 1995
    Assignee: The University of Maryland at Baltimore
    Inventors: Joseph R. Lakowicz, Engin U. Akkaya
  • Patent number: 5281825
    Abstract: A method and apparatus for using a square wave- or sinewave-driven electroluminescent lamp (ELL) as a source of periodically pulsed excitation light for a luminescent molecule, wherein changes in decay time, phase angle and/or modulation of the emitted luminescence are detected as parameters that correspond to changes in luminescence lifetimes.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: January 25, 1994
    Assignee: The University of Maryland School of Medicine
    Inventors: Klaus W. Berndt, Joseph R. Lakowicz
  • Patent number: 5246867
    Abstract: A method for measuring the concentration of a saccharide, conjugated saccharide or polysaccharide of interest using luminescent lifetimes and energy transfer in which an energy transfer donor-acceptor pair is added to a sample to be analyzed, the donor of the donor-acceptor pair being photoluminescent. The acceptor is bound to a carrier, while the donor and any saccharide, conjugated saccharide or polysaccharide of interest present in the sample compete for binding sites on the carrier. The sample is irradiated and the resultant emission detected. Energy transfer occurs between the donors and the acceptors, which produces a detectable lifetime change of the fIuorescence of the donor. The lifetime change is reduced or even eliminated by the competitive binding of a saccharide, conjugated saccharide or polysaccharide of interest to the donor. By measuring the apparent luminescent lifetime, the amount of a saccharide, conjugated saccharide or polysaccharide of interest in the sample can be determined.
    Type: Grant
    Filed: January 17, 1992
    Date of Patent: September 21, 1993
    Assignees: University of Maryland at Baltimore, Becton Dickinson & Company
    Inventors: Joseph R. Lakowicz, Badri P. Maliwal, Peter A. Koen
  • Patent number: 5196709
    Abstract: A method and apparatus for detecting the change in phase angle and/or modulation of emitted fluorescence of a fluorophore excited by modulated light from a laser diode. The light is both monochromatic and coherent, and can contain harmonic frequency components. The laser diode can be used in frequency-domain or phase-modulation measurements of fluorescence, using either phase or modulation techniques. The present invention is an improvement of the prior use of a frequency-doubled, cavity-dumped, dye laser in fluorometers. The invention provides an inexpensive light excitation source that is small in size, easily manageable, allows for short measurement times, and has lower power requirements.
    Type: Grant
    Filed: May 3, 1991
    Date of Patent: March 23, 1993
    Assignee: University of Maryland Systems
    Inventors: Klaus W. Berndt, Ignacy Gryczynski, Joseph R. Lakowicz