Tomas B Hirschfeld

45999015, Jul 15, 1986

Nov 28, 1984

6/675633

Tomas B. Hirschfeld - Livermore CA

University of California - Berkeley CA

G01L 708

73705

An apparatus is provided for sensing changes in pressure and for generating optical signals related to said changes in pressure. Light from a fiber optic illuminates a fluorescent composition causing it to fluoresce. The fluorescent composition is caused to more relative to the end of the fiber optic in response to changes in pressure so that the intensity of fluorescent emissions collected by the same fiber optic used for illumination varies monotonically with pressure.

52427978, Sep 7, 1993

Jan 2, 1992

7/817942

Tomas B. Hirschfeld - Livermore CA

C12Q 168
C12Q 170
G01N 3300
G01N 3348

435 6

An assay for polynucleotides employing total internal reflection of excitation radiation at a coating bonded to the surface of an optically conductive glass cell. The coating initially includes single-stranded polynucleotides coupled to individual attachment sites on the surface of the cell, such polynucleotides being complementary, at least in part to the single-stranded form of the polynucleotide that is being assayed. Each molecule of the coupled polynucleotide is connected to the cell surface through a spacer connected to an irreversibly conjugated polyadenine/polythymidine sequence at one end of the coupled polynucleotide. When the surface of the coated cell is contacted with a sample that contains single-stranded polynucleotide complementary to the bound polynucleotide, renaturation will occur, forming a double-stranded form of the polynucleotide of interest. A fluorochrome dye specific to that double-stranded form is coupled to the latter, the dye including a chromophore that the excitation radiation will excite into fluorescence. The induced fluorescence is then gathered and measured.

45960364, Jun 17, 1986

Aug 31, 1983

6/528284

Richard M. Norgren - Palo Alto CA
Joe W. Gray - Livermore CA
Tomas B. Hirschfeld - Livermore CA

The United States of America as represented by the United States
Department of Energy - Washington DC

G06K 900
G01N 1502

382 6

Apparatus and method are provided for analyzing sub-micron-sized features of microscopic particles. Two central features of the invention are (1) constraining microscopic particles to flow with substantially constant orientation through a predetermined interference fringe pattern, and (2) estimating particle structure by analyzing its fringe profile. The invention allows nearly an order of magnitude higher resolution of chromosome structure than possible with currently available flow system techniques. The invention allows rapid and accurate flow karyotyping of chromosomes.

45828091, Apr 15, 1986

Aug 9, 1982

6/406324

Myron J. Block - North Salem NH
Tomas B. Hirschfeld - Livermore CA

G01N 3353
G01N 33533
G01N 33552
G01N 2164

436527

A method and apparatus for fluorescent immunoassay utilizes total internal reflection at the interface between a solid phase and a liquid phase of lower index of refraction to produce an evanescent wave in the liquid phase. The solid phase is arranged and illuminated so as to provide multiple total internal reflections at the interface. In a preferred embodiment, the solid phase is in the form of an optical fiber to which is immobilized a component of the complex formed in the immunochemical reaction. A fluorophore is attached to another component of the complex. The fluorescent labelled component may be either the complement to or an analog of the immobilized component, depending on whether competitive or sandwich assays are to be performed. In the case of competitive assays, the labelled component is preferably pre-loaded to the immobilized component in a controlled concentration. The fiber (and the attached constituent of the assay) is immersed in the liquid phase sample.

48030490, Feb 7, 1989

Dec 12, 1984

6/681487

Tomas B. Hirschfeld - Livermore CA
Francis T. Wang - Danville CA

The Regents of the University of California - Berkeley CA

G01N 2180
G01N 3349

422 58

An apparatus is provided for remotely monitoring pH. A support material is provided on which organic dye molecules are covalently attached at a surface density falling within a predetermined range. The pH dependent fluorescence response of the bound organic dye molecules depends critically on surface density of the organic dye molecules bound to the support material and the nature of the covalent linkage betwen the organic dye molecules and the support material. The invention is operated by contacting the support material on which the organic dye is attached with the fluid whose pH is to be determined. When in contact, the organic dye on the support material is illuminated so that it is caused to fluoresce. The intensity of organic dye fluorescence is then related to pH.

45771090, Mar 18, 1986

Nov 30, 1982

6/445619

Tomas B. Hirschfeld - Livermore CA

Regents of the University of California - Berkeley CA

G01N 2164

2504611

A technique for gathering specific information from various remote locations, especially fluorimetric information characteristic of particular materials at the various locations is disclosed herein. This technique uses a single source of light disposed at still a different, central location and an overall optical network including an arrangement of optical fibers cooperating with the light source for directing individual light beams into the different information bearing locations. The incoming light beams result in corresponding displays of light, e. g. , fluorescent light, containing the information to be obtained. The optical network cooperates with these light displays at the various locations for directing ongoing light beams containing the same information as their cooperating displays from these locations to the central location. Each of these outgoing beams is applied to a detection arrangement, e. g. , a fluorescence spectroscope, for retrieving the information contained thereby.

47373431, Apr 12, 1988

Jan 21, 1986

6/820122

Tomas B. Hirschfeld - Livermore CA

The Regents of the University of California - Berkeley CA

G01N 2177
G01N 33497

422 63

An optrode is provided for sensing dissolved gases or volatile components of a solution. A fiber optic is provided through which light from an associated light source is transmitted from a first end to a second end. A bubble forming means, such as a tube, is attached to the second end of the fiber optic, and an indicator material is disposed in cooperation with the bubble forming means adjacent to the second end of the fiber optic such that it is illuminated by light emanating from the second end. The bubble forming means causes a gas bubble to form whenever the optrode is immersed in the fluid. The gas bubble separates the indicator material from the fluid. Gases, or other volatile components, of the fluid are sensed as they diffuse across the gas bubble from the fluid to the indicator material.

47848111, Nov 15, 1988

Mar 3, 1986

6/835357

Tomas B. Hirschfeld - Livermore CA

The Regents of the University of California - Berkeley CA

B29D 1100

264 14

A method of making optrodes is provided by which a pressure-sensitive volume is incorporated in the optrode by bubble transfer and/or gas entrapment in the manufacturing step sequence.