R. Ianniello, Alexander M. Yacynch
1983
Citations
0
Influential Citations
35
Citations
Journal
Analytica Chimica Acta
Abstract
Abstract An. iridium dioxide electrode with immobilized urease is useful as a potentiometric detector for pH changes resulting from hydlolysis of urea at the electrode suface. Electrodes constructed by urease entrapment in a poly(vinyl chloride) film are superior to electrodes with urease covalently immobilized to the oxide layer via a cyanuric chloride linkage. Logarithmic response is obtained for the dip-coated electrode over the range 5 × 10 -5 –5 × 10 -3 M urea with a slope of –51 mV/decade. The slope remains constant for approximately 12 days. Recoating a stripped electrode with PVC-urease has essentially no effect on the slope.