Patents by Inventor Diether Ruppel

Diether Ruppel 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).

  • Microencapsulation of biologically active material
    Patent number: 5100673
    Abstract: Polyelectrolyte membrane capsules are composed of a semi-permeable membrane and an active material enclosed by it, the membrane being formed of a biocompatible, non-toxic polyacid and a polybase; the polybase is composed of repeating monomer units of the formula (I) ##STR1## in which R.sup.1 and R.sup.2 have the indicated meanings.
    Type: Grant
    Filed: February 21, 1990
    Date of Patent: March 31, 1992
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hebert Bader, Karl-Heinz Keil, Diether Ruppel, Merten Schlingmann, Axel Walch
  • Biodegradable poly(hydroxyalkyl)amino dicarboxylic acid) derivatives, a process for their preparation, and the use thereof for depot formulations with controlled deivery of active ingredient
    Patent number: 5041291
    Abstract: The invention relates to biodegradable poly((hydroxyalkyl)amino dicarboxylic acid) derivatives of the formula I ##STR1## in which n, m, x, y, z, R and R' have the indicated meanings, and to a process for their preparation and to the use thereof for depot formulations with controlled delivery of active ingredient.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: August 20, 1991
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hubert Bader, Diether Ruppel, Axel Walch
  • Biodegradable poly(hydroxyalkyl)amino dicarboxylic acid) derivatives, a process for their preparation, and the use thereof for depot formulations with controlled delivery of active ingredient
    Patent number: 4906473
    Abstract: The invention relates to biodegradable poly((hydroxyalkyl)amino dicarboxylic acid) derivatives of the formula I ##STR1## in which n, m, x, y, z, R and R' have the indicated meanings, and to a process for their preparation and to the use thereof for depot formulations with controlled delivery of active ingredient.
    Type: Grant
    Filed: December 31, 1987
    Date of Patent: March 6, 1990
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hubert Bader, Diether Ruppel, Axel Walch
  • Biologically degradable polyamide for depot preparations having controlled release of the active compound
    Patent number: 4835248
    Abstract: Polyamides in which amino acids are incorporated in the polymer backbone via two amino or carboxyl groups and which carry in the .alpha.-position to the amide structure a functional group which is responsible for degradation and active compound release are highly suitable for the preparation of biologically degradable active compound depot preparations having controlled release of the active compound.
    Type: Grant
    Filed: May 13, 1987
    Date of Patent: May 30, 1989
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hubert Bader, Diether Ruppel, Axel Walch, Michael Magerstadt