SOYBEAN-MEAL TISSUE BASED MEMBRANE BIOELECTRODE FOR UREA

Novel potentiometric membrane electrodes with high selectivity to urea over the 1.3 x 10(-4)-1.1 x 10(-2) M and 4.0 x 10(-4)-1.0 x 10(-2) M concentration range were constructed by immobilized soybean meal at a NH3 or CO2 gas-sensing electrode. The sensor does not require fresh bean tissue so it is not limited by the season of the year. The influence of some experimental parameters, including buffer composition, pH, and immobilization techniques are discussed. The resulting electrode is found to be a viable alternative to the enzyme-based electrode.