Biopolym. Cell. 1997; 13(5):377-379.
Structure and Function of Biopolymers
Urease-based biosensor with improved sensitivity for heavy metal ions analysis
1Soldatkin A. P.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680


Potcntiometric biosensors which consist of two ISFET structures covered with immobilized enzyme (urease) can be used for quantitative estimation, of water pollution with heavy metal ions. The measurements of the residual enzyme activity have been carried out in Tris-HCl buffer (pH 7,4) after preincubation in model CuCl2 solution. It was shown that sensor sensitivity to inhibitor concentration depends strongly on enzyme immobilization method. The lowest detection limit has been obtained for urease biosensor modified by negatively charged additional Nafion membrane.


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