Development of N(2) Sensor for Determination of PN(2) in Body Tissues.
Final rept. 15 Jun 83-14 Jun 86,
EIC LABS INC NORWOOD MA
Pagination or Media Count:
Experiments were performed to identify transition metal ion-dinitrogen complex systems whose chemical and electrochemical properties would be favorable for use in quantitating PN2, and to develop methods of immobilizing those metal ions so that the reactions of interest would take place on an electrode surface. A N2 sensing systems was developed which is comprised of an ion exchange polymer membrane Nafion, containing RuIII cations coated onto a glassy carbon electrode. The electrode is activated for N2 measurement by applying a reducing potential to generate the N2-complexing RUII cation on the electrod surface. The surface RuII cation reacts with N2 in solution to form a surface RUII-N2 complex. This complex is electrochemically detectable and distinguishable from the RUII precursor. At short times, the reaction follows first-order kinetic with a rate constand 10 times greater than for the equibalent homogeneous reaction. The reaction rate is proportional to PN2 up to 8 atm and possible higher. The sensitivity approaches 110 atmosphere and the minimum electrode response time at elevated PN2 is 10 sec. This N2 sensing system holds promise for eventual configuration into an implantable unit for in situ measurements of tissue PN2 during compression and decompression of an experimental animal.
- Physical Chemistry