Patents by Inventor Peter D. Van der Wal

Peter D. Van der Wal 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).

  • Membrane selective for metal ions
    Patent number: 5238548
    Abstract: An ionophore according to the general formula I wherein the substituents are chosen such that the ionophore is either also polymerized in the matrix of a membrane selective for metal ions or interwoven therewith. Thus obtained is a membrane having a long useful life for use in diverse sensors such as ISFET, ion-selective electrode, and the like.
    Type: Grant
    Filed: May 18, 1992
    Date of Patent: August 24, 1993
    Assignee: Priva Agro Holding B.V.
    Inventors: Peter D. van der Wal, Udo H. Verkerk, Gerardus W. N. Honig, Hermanus A. J. Holterman, Jan R. Haak, David N. Reinhoudt
  • Process for manufacturing a REFET or a CHEMFET, and the manufactured REFET or CHEMFET
    Patent number: 4882292
    Abstract: The invention relates to a process for manufacturing a REFET and/or CHEMFET, comprising: (a) covalent bonding of a hydrophilic polymer layer to an isolator layer applied to a semiconductor material; (b) the absorption of water or a watery solution into said hydrophilic polymer layer; and (c) the binding of a hydrophobic polymer layer to the water holding hydrophilic polymer layer. It is advantageous that this water holding hydrophilic polymer layer also contains an electrolyte and/or a buffer.Preferably an ion to be measured with the CHEMFET also forms part of the electrolyte.
    Type: Grant
    Filed: September 4, 1987
    Date of Patent: November 21, 1989
    Assignee: Stichting Centrum voor Micro-Elektronics Twente
    Inventors: Ernst J. Sudholter, Maria D. Skowronska-Ptasinska, Peter D. Van der Wal, Albert Van den Berg, David N. Reinhoudt