Patents by Inventor Rajan P. Kulkarni

Rajan P. Kulkarni 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: 7781217
    Abstract: Resonant sensors and methods of detecting specific molecules with enhanced sensitivity. Optical energy is introduced into a microcavity, such as a silica toroid-shaped microcavity. The microcavity sensor has a functionalized outer surface and a sufficiently high Q value to generate an evanescent optical field with increased intensity. A molecule bound to the functionalized outer surface interacts with the external optical field, thereby heating the microcavity and generating a detectable resonant wavelength shift, which indicates a small number of molecules, even a single molecule, without the use of fluorescent or metal labels. Resonant sensors and methods can also be used to detect specific molecules, even a single molecule, within an environment. One application is detecting very small quantities or a single molecule of heavy water in ordinary water.
    Type: Grant
    Filed: April 10, 2007
    Date of Patent: August 24, 2010
    Assignee: California Institute of Technology
    Inventors: Andrea M. Armani, Rajan P. Kulkarni, Scott E. Fraser, Kerry J. Vahala
  • Patent number: 6136187
    Abstract: A mixture of chromatographic particles and a solution of water, alcohol and metal alkoxide may be injected by means of a syringe into a capillary column as a gel. The volatile components in the gel are evaporated by means of heating and gas pressure reduction to form a porous sol-gel glass matrix attached to the inner wall of the separation channel. The pores are large enough for the passage of protons, neutral and ionic species but are too small to permit significant leaching of the chromatographic particles. The separation column so formed requires no frits to maintain the glass matrix in place in the column. Electrical potential difference and/or pressure difference may be applied to cause fluid flow in the separation column to cause electrophoretic and chromatographic separation.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: October 24, 2000
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Richard N. Zare, Maria T. Dulay, Rajan P. Kulkarni