Conductometric enzyme biosensors based on natural zeolite clinoptilolite for urea determination

Saiapina, O. Y.
Pyeshkova, V. M.
Soldatkin, O. O.
Melnik, V. G.
Akata Kurç, Burcu
Walcarius, A.
Dzyadevych, S. V.
Jaffrezic-Renault, N.
Highly sensitive conductometric urea biosensors were developed by exploiting the successful combination of ammonium-sieving and ion exchange properties of clinoptilolite, with a unique biorecognition capacity of urease. To optimize the performance of urea biosensors based on clinoptilolite, the dependences of their analytical signals on pH, buffer capacity and ionic strength of phosphate buffer solution (PBS) were studied. Optimum pH for urea biosensors was found within the range of pH 6.0-7.0. The dependences of biosensors responses on buffer capacity and ionic strength of PBS were of the same profile as those obtained for the urea biosensor which was not modified with clinoptilolite.


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Citation Formats
O. Y. Saiapina et al., “Conductometric enzyme biosensors based on natural zeolite clinoptilolite for urea determination,” MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS, pp. 1490–1497, 2011, Accessed: 00, 2020. [Online]. Available: