Reproducibility of responses to the 0.5 mM urea obtained with biosensors created by different methods of 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) and 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