Urease-based ISFET biosensor for arginine determination

In this work a novel biosensor for arginine determination based on the urease inhibition effect has been proposed. Ion-selective field effect transistors were used as transducers. Urease immobilized in glutaraldehyde vapor served as a biorecognition element of the biosensor. Significant part of the work was aimed at proving the urease inhibition by arginine. Optimal concentration of urea for arginine determination was chosen. Detection limit for arginine was 0.05 mM. The biosensor selectivity towards different amino acids was studied. The results of quantitative determination of l-arginine in the real sample (a drinkable solution “Arginine Veyron”) were in good agreement with the producerʹs data (a relative error was 5.2%). The biosensor showed a good reproducibility of arginine determination.