Implantable medical device including an arrangement for measuring a blood property having a carbon reference electrode

DETAILED DESCRIPTION We claim as our invention: 1.
An implantable medical device comprising: means for making an electrochemical measurement of a blood property including a reference electrode adapted for in vivo interaction with blood; and said reference electrode consisting of activated pyrolytic carbon.
2.
An implantable medical device as claimed in claim 1 wherein said means for making an electrochemical measurement includes a holder for said reference electrode, said holder consisting of titanium and having a surface in contact with said reference electrode, and an anti-oxidation material disposed between said surface and said reference electrode.
3.
An implantable medical device as claimed in claim 2 wherein said anti-oxidation material comprises a material selected from the group consisting of titanium nitride and titanium carbide.
4.
An implantable medical device as claimed in claim 1 wherein said means for making an electrochemical measurement includes a holder for said reference electrode, said holder consisting of gold.
5.
An implantable medical device as claimed in claim 1 wherein said means for making an electrochemical measurement includes a holder for said reference electrode, said holder consisting of platinum.




Description:
BACKGROUND OF THE INVENTION 1.
Field of the Invention The present invention relates to an implantable medical device for in-vivo electrochemical measurements of blood properties such as measurements of, inter alia, oxygen pressure, glucose and pH.
2.
Description of the Prior Art In electrochemical measurements a reference electrode is used to measure a reference potential and to relate the potentials of other electrodes to the reference potential, thereby making it possible to measure the blood property.
Electrochemical sensors and e.
g.
pacemakers, which are implanted in the body of a patient, require an implantable reference electrode with long-term stability.
In this context, the technical literature only proposes reference electrodes made of Ag/AgCl