Inter-reproducibility of signals to urea concentration. 0.5 mM (A) and 3.5 mM (B) obtained with biosensors created by urease immobilization in GA vapour (1), adsorption on the surface of transducer covered with monolayer of: silicalite (2), nano beta zeolite (3), zeolite L (4), calcinated nano beta zeolite (5). The measurements were carried out in 5 mM phosphate buffer solution (pH 7.4).
Shelyakina et al. Nanoscale Research Letters 2014 9:124 doi:10.1186/1556-276X-9-124