Patents by Inventor Indrajit Roy

Indrajit Roy 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).

  • Publication number: 20040180096
    Abstract: The present invention provides methods and compositions for photodynamic therapy. The composition comprises ceramic nanoparticles in which a photosensitive drug/dye is entrapped. The ceramic nanoparticles are made by formation of a micellar composition of the dye. The ceramic material is added to the micellar composition and the ceramic nanoparticles are precipitated by alkaline hydrolysis. The precipitated nanoparticles in which the photosensitive dye/drug is entrapped can be isolated by dialysis. The resulting drug doped nanoparticles are spherical, highly monodispersed, and stable in aqueous system. Irradiation with light of suitable wavelength of the photosensitizing drug entrapped inside nanoparticles resulted in generation of singlet oxygen, which was able to diffuse out through the pores of the ceramic matrix. The drug loaded ceramic nanoparticles of the present invention can be used as drug carriers for photodynamic therapy.
    Type: Application
    Filed: January 26, 2004
    Publication date: September 16, 2004
    Inventors: Paras Prasad, Indrajit Roy, Earl J. Bergey, Tymish Y. Ohulchansky, Haridas Pudavar
  • Patent number: 6555376
    Abstract: The present invention relates to a process of entrapping genetic materials in nanoparticles of inorganic metal salts of size below 100 nm diameter to form non-viral carriers for delivery of genes. The process comprises the steps of dissolving surfactants and a cosurfactant in oil to obtain reverse micelles. An aqueous solution of genetic material is added to the reverse micelles. Thereafter the reverse micelles are divided into two equal parts. To one part, aqueous solution of inorganic metal salts is dissolved to obtain optically clear and transparent reverse micelles. To the second part aqueous solution of precipitating agent is added to obtain optically clear and transparent reverse micelles. The two equally divided parts of reverse micelles are mixed to form inorganic nanopartcles encapsulating added genetic material. Thereafter, the nanoparticles are separated from reverse micelles, the inorganic nanoparticles are dispersed in water and dialyzed to remove free metal salts, surfactant and oil.
    Type: Grant
    Filed: July 24, 2002
    Date of Patent: April 29, 2003
    Assignee: University of Delhi, Department of Chemistry
    Inventors: Amarnath Maitra, Subho Mozumdar, Susmita Mitra, Indrajit Roy
  • Publication number: 20030027336
    Abstract: The present invention relates to a process of entrapping genetic materials in nanoparticles of inorganic metal salts of size below 100 nm diameter to form non-viral carriers for delivery of genes. The process comprises the steps of dissolving surfactants and a cosurfactant in oil to obtain reverse micelles. An aqueous solution of genetic material is added to the reverse micelles. Thereafter the reverse micelles are divided into two equal parts. To one part, aqueous solution of inorganic metal salts is dissolved to obtain optically clear and transparent reverse micelles. To the second part aqueous solution of precipitating agent is added to obtain optically clear and transparent reverse micelles. The two equally divided parts of reverse micelles are mixed to form inorganic nanoparticles encapsulating added genetic material. Thereafter, the nanoparticles are separated from reverse micelles, the inorganic nanoparticles are dispersed in water and dialyzed to remove free metal salts, surfactant and oil.
    Type: Application
    Filed: July 24, 2002
    Publication date: February 6, 2003
    Applicant: University of Delhi, an Indian University
    Inventors: Amarnath Maitra, Subho Mozumdar, Susmita Mitra, Indrajit Roy