IRIDIUM-DISPERSED CARBON-PASTE AMINO-ACID OXIDASE ELECTRODES

An amino acid biosensor based on the immobilization of L-or D-amino ac id oxidase within an iridium-dispersed carbon paste electrode is descr ibed. The strong and preferential electrocatalytic activity of iridium towards hydrogen peroxide allows rapid measurements of amino acids at very low potentials where the possibilities of interferences are mini mal. The detection limits, depending on the amino acid, are in the ord er of 10(-5) M. The influence of parameters such as flow rate, working potential, iridium and enzyme loadings are discussed.