Patents Assigned to Research Products Rehovot Ltd.
  • Patent number: 4413999
    Abstract: The invention provides amidoxime derivatives of the general formula ##STR1## wherein R.sub.1 is an alkyl group of 1 to 8 carbon atoms, phenyl, a heterocyclic ring structure of 5 to 8 atoms containing one or more nitrogen or oxygen atoms or combinations thereof or a bicyclic condensed ring system optionally containing at least one heterocyclic ring which groups may each be optionally substituted. R.sub.2 is a mono or bicyclic heterocyclic radical containing at least two nitrogen atoms which radical is also optionally substituted. R.sub.3 and R.sub.4 are independently H, or an alkyl of 1 to 4 carbon atoms or one, but not both, is ##STR2## and the other, H, wherein R.sub.5 or R.sub.6 are alkyls of 2 to 5 carbon atoms optionally substituted by R.sub.1, or a phenyl optionally substituted by R.sub.1 or R.sub.5 or R.sub.6 is combined with R.sub.1 to jointly form cyclic imidoximes or imidedioximes.
    Type: Grant
    Filed: March 5, 1982
    Date of Patent: November 8, 1983
    Assignee: Research Products Rehovot Ltd.
    Inventors: Charles Linder, Gershon Aviv
  • Patent number: 4251631
    Abstract: A cross-linked enzyme membrane is prepared by directly adsorbing enzymes into the pores of a microporous non-fibrous filter membrane made of a silica modified vinylchloride polymer and then cross-linking the enzyme with a bi-functional coupling agent whereby enzyme molecules are cross-linked to each other without chemically bonding the enzyme molecules to the membrane. The cross-linked enzyme membrane is used to carry out enzymatic reactions by passing a solution of substrate for the enzyme through the membrane under a pressure differential.
    Type: Grant
    Filed: February 1, 1979
    Date of Patent: February 17, 1981
    Assignee: Research Products Rehovot Ltd.
    Inventor: Shulamith Simon
  • Patent number: 4246092
    Abstract: The invention provides a method for the performance of selective electrodialytic separation of a first group of charged ions from a solution containing other charged ions having the same sign and optionally the same valence as said first group comprising applying a current to an electrodialysis unit comprising at least one thin, dense, non-porous charged electrodialysis membrane made of water-insoluble hydrophobic polymeric material, containing covalently bound ionizable groups, wherein said membrane separates at least one diluting compartment from at least one concentrating compartment in said unit and wherein said membrane is in the form of a polymeric matrix optionally supported on a porous support and having a preselected dielectric constant and composition adapted to induce selective ion disassociation of said first group of charged ions whereby there is achieved a substantial ion migration of said selected ion group and its preferential transference across said membrane at a fraction larger than its rel
    Type: Grant
    Filed: December 28, 1978
    Date of Patent: January 20, 1981
    Assignee: Research Products Rehovot Ltd.
    Inventors: Mordechai Perry, Charles Linder, Ora Kedem
  • Patent number: 4238307
    Abstract: The invention provides a process for the separation, by electrodialysis, of a mixed aqueous solution, containing an essential amino acid and a derivative of that acid as components therof, wherein one of said components is in charged form and the other of said components is in amphoteric form, into at least two separate product solutions, of acid and derivative respectively, of which at least one product solution contains highly pure product obtained at high quantitative yield, comprising providing an electrodialysis stack, continuously introducing a feed solution containing an essential amino acid and derivative thereof to be separated into feed cells of the stack, adjusting the flow rate and concentration of the solution and the electric current density applied to values adapted to create concentration polarization conditions adjacent to the membranes in the feed cell thereby accumulating a high local concentration of protons upon the surface of the anion exchange membranes, and a high local concentration o
    Type: Grant
    Filed: February 14, 1979
    Date of Patent: December 9, 1980
    Assignee: Research Products Rehovot Ltd.
    Inventors: Mordechai Perry, Ora Kedem
  • Patent number: 4238306
    Abstract: The invention provides a process for the separation, by electrodialysis, of a mixed aqueous solution containing a non-essential amino acid and a derivative of that acid in ionic form, into at least two separate product solutions of acid and derivative respectively, of which at least one solution contains highly pure product obtained at high quantitative yield, comprising providing an electrodialysis stack, continuously introducing a feed solution containing a non-essential amino acid and derivative thereof to be separated into feed cells of the stack, adjusting the flow rate and concentration of the solution and the electric current density applied to values adapted to create concentration polarization conditions adjacent to the membranes in the feed cells thereby accumulating a high local concentration of protons upon the surface of the anion exchange membranes, and a high local concentration of hydroxyl ions upon the cation exchange membranes and maintaining the pH of the bulk solution in the feed cells in
    Type: Grant
    Filed: February 14, 1979
    Date of Patent: December 9, 1980
    Assignee: Research Products Rehovot Ltd.
    Inventors: Mordechai Perry, Ora Kedem
  • Patent number: 4101380
    Abstract: The invention relates to a process for the cross-linking of proteins wherein the proteins to be cross-linked are reacted with a cross-linking agent selected from the group consisting of:(a) water soluble poly(ethylene oxide) derivatives of the general formula I(z).sub.m --Y--(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH.sub.2 --Y--(Z).sub.
    Type: Grant
    Filed: June 11, 1976
    Date of Patent: July 18, 1978
    Assignee: Research Products Rehovot Ltd.
    Inventors: Menachem Rubinstein, Shulamit Simon, Rene Bloch, deceased