polyaniline-multiwalled carbon nanotubes (PANI/MWCNTs) composite were fabricated by electropolymerization method.Urease has been immobilized by using physical adsorption and electrochemical entrapment technique. A conventional three-electrode system was used. Pencil graphite disk electrode (PGDE), Ag/AgCl (3 M KCl) and platinum wire were used
as working electrode, reference electrode and counter electrode respectively. The influence of several experimental parameters such as applied potential, type and concentrate of dopant and enzyme loading was explored to optimize the electroanalytical performance ofthe biosensor. The responses ofthe enzyme electrodes were measured via monitoring amperometric current at +0.3V (vs. Ag/AgCl)