Patents by Inventor Anand Natrajan

Anand Natrajan 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: 7875467
    Abstract: Chemiluminescent acridinium compounds are used in homogeneous assays to determine the concentration of an analyte in a sample without strong acid or strong base treatment. The chemiluminescent acridinium compounds include acridinium esters with electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus to inhibit pseudo-base formation, or acridinium sulfonamides with or without electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: January 25, 2011
    Assignee: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand A. Natrajan, Todd Sells, Hartmut Schroeder, Guohan Yang, David Sharpe, Qingping Jiang, Hana Lukinsky, Say-Jong Law
  • Publication number: 20100256380
    Abstract: A method is provided for N-alkylation of acridine compounds, typically with a 1,3-propane sultone alkylating reagent, in ionic liquid solvents to provide the corresponding acridinium compounds in high yield.
    Type: Application
    Filed: November 18, 2008
    Publication date: October 7, 2010
    Applicant: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand Natrajan, David Wen
  • Patent number: 7785904
    Abstract: The present invention relates to hydrophilic, high quantum yield acridinium compounds. It has been discovered that the placement of electron-donating groups in the acridinium ring system increases the amount of light that is emitted by the corresponding acridinium compound when its chemiluminescence is triggered by alkaline peroxide. More specifically, it has been found that the placement of one or two hydrophilic, alkoxy groups at the C-2 and/or C-7 position of the acridinium ring system of acridinium compounds increases their quantum yield and enhances the aqueous solubility of these compounds. The present hydrophilic, high quantum yield, acridinium compounds are useful chemiluminescent labels for improving the sensitivity of immunoassays.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: August 31, 2010
    Assignee: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, James Costello
  • Publication number: 20100099077
    Abstract: Chemiluminescent acridinium esters are provided which are fast light emitting and hydrolytically stable. The chemiluminescent acridinium esters are useful labels in assays for detecting or quantifying analytes.
    Type: Application
    Filed: October 15, 2007
    Publication date: April 22, 2010
    Applicant: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe
  • Publication number: 20090318627
    Abstract: Acridinium-functionalized solid-phase supports and methods for making acridinium-functionalized solid-phase supports are disclosed. The acridinium-functionalized solid-phase supports comprise a solid phase support linked to a chemiluminescent substituted acridinium compound through a linker group covalently attached to the nitrogen atom of the acridinium nucleus and the solid phase support as exemplified in FIG. 1.
    Type: Application
    Filed: February 6, 2007
    Publication date: December 24, 2009
    Applicant: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand Natrajan, David Sharpe, Jim Costello, Qingping Jiang
  • Patent number: 7611909
    Abstract: A method for the detection or quantitation of unlabeled target analyte in a biological sample, the method comprising labeling a target analyte for a biological sample suspected of containing unlabeled target analyte with an acridinium compound to form a labeled target analyte and providing the labeled target analyte to the biological sample, or providing the labeled target analyte to the biological sample, wherein the acridinium compound comprises an acridinium nucleus having an electron-donating substituent directly attached to the acridinium nucleus, with the electron-donating substituent attached at the C2 position. Chemiluminescent acridinium compounds useful in the method have emission maxima close to or in the near infrared (NIR) region (>590 nm).
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: November 3, 2009
    Assignee: Siemens Healthcare Diagnostics Inc.
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, Say-Jong Law
  • Publication number: 20090029349
    Abstract: Chemiluminescent acridinium compounds are used in homogeneous assays to determine the concentration of an analyte in a sample without strong acid or strong base treatment. The chemiluminescent acridinium compounds include acridinium esters with electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus to inhibit pseudo-base formation, or acridinium sulfonamides with or without electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus.
    Type: Application
    Filed: November 21, 2007
    Publication date: January 29, 2009
    Applicant: Siemens Medical Solutions Diagnostics
    Inventors: Anand A. Natrajan, Todd Sells, Hartmut Schroeder, Guohan Yang, David Sharpe, Qingping Jiang, Hana Lukinsky, Say-Jong Law
  • Publication number: 20080305557
    Abstract: Chemiluminescent acridinium compounds are used in homogeneous assays to determine the concentration of an analyte in a sample without strong acid or strong base treatment. The chemiluminescent acridinium compounds include acridinium esters with electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus to inhibit pseudo-base formation, or acridinium sulfonamides with or without electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus.
    Type: Application
    Filed: November 21, 2007
    Publication date: December 11, 2008
    Applicant: Siemens Medical Solutions Diagnostics
    Inventors: Anand Natrajan, Todd Sells, Hartmut Schroeder, Guohan Yang, David Sharpe, Qingping Jiang, Hana Lukinsky, Say-Jong Law
  • Patent number: 7459284
    Abstract: A chemiluminescent substrate of a hydrolytic enzyme having the following general Formula I is disclosed, as follows: Lumi-M-P??Formula I where “Lumi” is a chemiluminescent moiety capable of producing light (a) by itself, (b) with MP attached and (c) with M attached. Examples of Lumi include chemiluminescent acridinium compounds, benzacridinium compounds, quinolinium compounds, isoquinolinium compounds, phenanthridinium compounds, and lucigenin compounds, spiroacridan compounds, luminol compounds and isoluminol compounds. M is a multivalent heteroatom having at least one lone pair of electrons selected from oxygen, nitrogen and sulfur, directly attached to the light emitting moiety of Lumi at one end and to P at the other end. P is a group that can be readily removed by hydrolytic enzymes. An enzymatic reaction utilizing the above compound is the following: where HE is a hydrolytic enzyme. Lumi-M is a chemiluminescent product having physical and/or chemical properties different from those of Lumi-M-P.
    Type: Grant
    Filed: June 5, 2006
    Date of Patent: December 2, 2008
    Assignee: Siemens Healthcare Diagnostics Inc.
    Inventors: Qingping Jiang, Anand Natrajan, David Sharpe, Wen-Jee Wong, Say-Jong Law
  • Publication number: 20080014660
    Abstract: The present invention relates to hydrophilic, high quantum yield acridinium compounds. It has been discovered that the placement of electron-donating groups in the acridinium ring system increases the amount of light that is emitted by the corresponding acridinium compound when its chemiluminescence is triggered by alkaline peroxide. More specifically, it has been found that the placement of one or two hydrophilic, alkoxy groups at the C-2 and/or C-7 position of the acridinium ring system of acridinium compounds increases their quantum yield and enhances the aqueous solubility of these compounds. The present hydrophilic, high quantum yield, acridinium compounds are useful chemiluminescent labels for improving the sensitivity of immunoassays.
    Type: Application
    Filed: June 19, 2007
    Publication date: January 17, 2008
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, James Costello
  • Patent number: 7319041
    Abstract: Chemiluminescent acridinium compounds are used in homogeneous assays to determine the concentration of an analyte in a sample without strong acid or strong base treatment. The chemiluminescent acridinium compounds include acridinium esters with electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus to inhibit pseudo-base formation, or acridinium sulfonamides with or without electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: January 15, 2008
    Assignee: Siemens Medical Solutions Diagnostic
    Inventors: Anand Natrajan, Todd Sells, Hartmut Schroeder, Guohan Yang, David Sharpe, Qingping Jiang, Hana Lukinsky, Say-Jong Law
  • Patent number: 7309615
    Abstract: The present invention relates to hydrophilic, high quantum yield acridinium compounds. It has been discovered that the placement of electron-donating groups in the acridinium ring system increases the amount of light that is emitted by the corresponding acridinium compound when its chemiluminescence is triggered by alkaline peroxide. More specifically, it has been found that the placement of one or two hydrophilic, alkoxy groups at the C-2 and/or C-7 position of the acridinium ring system of acridinium compounds increases their quantum yield and enhances the aqueous solubility of these compounds. The present hydrophilic, high quantum yield, acridinium compounds are useful chemiluminescent labels for improving the sensitivity of immunoassays.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: December 18, 2007
    Assignee: Siemens Medical Solutions Diagnostic
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, James Costello
  • Publication number: 20060202179
    Abstract: A chemiluminescent substrate of a hydrolytic enzyme having the following general Formula I is disclosed, as follows: Lumi-M-P ??Formula I where “Lumi” is a chemiluminescent moiety capable of producing light (a) by itself, (b) with MP attached and (c) with M attached. Examples of Lumi include chemiluminescent acridinium compounds, benzacridinium compounds, quinolinium compounds, isoquinolinium compounds, phenanthridinium compounds, and lucigenin compounds, spiroacridan compounds, luminol compounds and isoluminol compounds. M is a multivalent heteroatom having at least one lone pair of electrons selected from oxygen, nitrogen and sulfur, directly attached to the light emitting moiety of Lumi at one end and to P at the other end. P is a group that can be readily removed by hydrolytic enzymes. An enzymatic reaction utilizing the above compound is the following: where HE is a hydrolytic enzyme. Lumi-M is a chemiluminescent product having physical and/or chemical properties different from those of Lumi-M-P.
    Type: Application
    Filed: June 5, 2006
    Publication date: September 14, 2006
    Applicant: BAYER CORPORATION
    Inventors: Qingping Jiang, Anand Natrajan, David Sharpe, Wen-Jee Wong, Say-Jong Law
  • Patent number: 7097995
    Abstract: A chemiluminescent substrate of a hydrolytic enzyme having the following general Formula I is disclosed, as follows: Lumi-M-PFormula I where “Lumi” is a chemiluminescent moiety capable of producing light (a) by itself, (b) with MP attached and (c) with M attached. Examples of Lumi include chemiluminescent acridinium compounds, benzacridinium compounds, quinolinium compounds, isoquinolinium compounds, phenanthridinium compounds, and lucigenin compounds, spiroacridan compounds, luminol compounds and isoluminol compounds. M is a multivalent heteroatom having at least one lone pair of electrons selected from oxygen, nitrogen and sulfur, directly attached to the light emitting moiety of Lumi at one end and to P at the other end. P is a group that can be readily removed by hydrolytic enzymes. An enzymatic reaction utilizing the above compound is the following: where HE is a hydrolytic enzyme. Lumi-M is a chemiluminescent product having physical and/or chemical properties different from those of Lumi-M-P.
    Type: Grant
    Filed: August 27, 2004
    Date of Patent: August 29, 2006
    Assignee: Bayer Corp.
    Inventors: Qingping Jiang, Anand Natrajan, David J. Sharpe, Wen-Jee Wong, Say-Jong Law
  • Patent number: 7083986
    Abstract: A method for the detection or quantitation of an analyte in a biological sample is disclosed. The method comprises the steps of selecting a biological sample suspected of containing a target analyte and binding the target analyte in the sample to a binding partner conjugated to an acridinium compound, wherein the acridinium compound comprises an acridinium nucleus having an electron-donating substituent directly attached to the acridinium nucleus at the C2 position. Chemiluminescent acridinium compounds useful in the method have emission maxima close to or in the near infrared (NIR) region (>590 nm). These chemiluminescent acridinium compounds when used in conjunction with short wavelength-emitting acridinium esters (with emission maxima below 450 nm) can be highly useful labels for the simultaneous detection of multiple target analytes in a single assay.
    Type: Grant
    Filed: December 6, 2001
    Date of Patent: August 1, 2006
    Assignee: Bayer Healthcare LLC
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, Say-Jong Law
  • Publication number: 20050221390
    Abstract: The present invention relates to hydrophilic, high quantum yield acridinium compounds. It has been discovered that the placement of electron-donating groups in the acridinium ring system increases the amount of light that is emitted by the corresponding acridinium compound when its chemiluminescence is triggered by alkaline peroxide. More specifically, it has been found that the placement of one or two hydrophilic, alkoxy groups at the C-2 and/or C-7 position of the acridinium ring system of acridinium compounds increases their quantum yield and enhances the aqueous solubility of these compounds. The present hydrophilic, high quantum yield, acridinium compounds are useful chemiluminescent labels for improving the sensitivity of immunoassays.
    Type: Application
    Filed: June 2, 2005
    Publication date: October 6, 2005
    Applicant: Bayer HealthCare LLC
    Inventors: Anand Natrajan, Qingping Jiang, David Sharpe, James Costello
  • Publication number: 20050032147
    Abstract: A chemiluminescent substrate of a hydrolytic enzyme having the following general Formula I is disclosed, as follows: Lumi-M-P??Formula I where “Lumi” is a chemiluminescent moiety capable of producing light (a) by itself, (b) with MP attached and (c) with M attached. Examples of Lumi include chemiluminescent acridinium compounds, benzacridinium compounds, quinolinium compounds, isoquinolinium compounds, phenanthridinium compounds, and lucigenin compounds, spiroacridan compounds, luminol compounds and isoluminol compounds. M is a multivalent heteroatom having at least one lone pair of electrons selected from oxygen, nitrogen and sulfur, directly attached to the light emitting moiety of Lumi at one end and to P at the other end. P is a group that can be readily removed by hydrolytic enzymes. An enzymatic reaction utilizing the above compound is the following: where HE is a hydrolytic enzyme. Lumi-M is a chemiluminescent product having physical and/or chemical properties different from those of Lumi-M-P.
    Type: Application
    Filed: August 27, 2004
    Publication date: February 10, 2005
    Inventors: Qingping Jiang, Anand Natrajan, David Sharpe, Wen-Jee Wong, Say-Jong Law
  • Patent number: 6783948
    Abstract: A chemiluminescent substrate of hydrolytic enzyme having the following general Formula I, as follows: Lumi-M-P  Formula I where “Lumi” is a chemiluminescent moiety capable of producing light (a) by itself, (b) with MP attached and (c) with M attached. Examples of Lumi include chemiluminescent acridinium compounds, benzacridinium compounds, quinolinium compounds, isoquinolinium compounds, phenanthridinium compounds, and lucigenin compounds, spiroacridan compounds, luminol compounds and isoluminol compounds. M is a multivalent heteroatom having at least one lone pair of electrons selected from oxygen, nitrogen and sulfur, directly attached to the light emitting moiety of Lumi at one end and to P at the other end. P it a group that can be readily removed by hydrolytic enzymes.
    Type: Grant
    Filed: July 27, 2000
    Date of Patent: August 31, 2004
    Assignee: Bayer Corporation
    Inventors: Qingping Jiang, Anand Natrajan, David J. Sharpe, Wen-Jee Wong, Say-Jong Law
  • Publication number: 20040063147
    Abstract: Chemiluminescent acridinium compounds are used in homogeneous assays to determine the concentration of an analyte in a sample without strong acid or strong base treatment. The chemiluminescent acridinium compounds include acridinium esters with electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus to inhibit pseudo-base formation, or acridinium sulfonamides with or without electron donating functional groups at the C2 and/or C7 position on the acridinium nucleus.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 1, 2004
    Applicant: BAYER CORPORATION
    Inventors: Anand Natrajan, Todd Sells, Hartmut Schroeder, Guohan Yang, David Sharpe, Qingping Jiang, Hana Lukinsky, Say-Jong Law
  • Patent number: 6673560
    Abstract: The present invention discloses a method for the measurement of hydride using a chemiluminescent compound. The preferred chemiluminescent molecule is an acridinium compound. The source of hydride for the reduction of acridinium compound may be of chemical or biochemical origin, or the result of enzymatic catalysis. The chemical source of hydride, for example, might be metal hydrides, such as NaBH4. A biochemical source of hydride might be that derived from NADH, or NADPH, while an enzymatic source would be the class of oxidoreductases termed dehydrogenases which convert NADH or NADPH from NAD or NADP. There are numerous potential applications for acridinium compounds as chemiluminescent indicators of hydride. Any applied tests or diagnostic assays, in which hydride is either present at the onset of or generated through the course of a reaction, would benefit from the present invention.
    Type: Grant
    Filed: November 23, 1999
    Date of Patent: January 6, 2004
    Assignee: Bayer Corporation
    Inventors: David Sharpe, Anand Natrajan, Qingping Jiang, George Parsons, Say-Jong Law