Biopolym. Cell. 1996; 12(1):53-57.
http://dx.doi.org/10.7124/bc.000412
Conductometric urease microbiosensor based on thin-film interdigitated electrodes for urea determination
1Dzyadevich S. V., 1Zhylyak G. A., 1Soldatkin A. P., 1El'skaya A. V.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680

Abstract

The characteristics of conductometric urease microbiosensor based on thin-film inter-digitated electrodes for urea determination have been studied. Urease has been immobilized by cross-linking with bovine serumalbumin using glutaraldehyde. The resulting conductivity changes are produced by enzymatically catalyzed hydrolysis of urea. This process for both immobilized enzyme and soluble one is described by the classic laws of enzymatic kinetics. The influence of ionic strength, pH and buffer capacity of the samples on the biosensor response has been thoroughly tested. The results have been discussed concerning urea concentration analysis in human blood.
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