NiO nanoparticle-based urea biosensor

► NiO nanoparticles (NiO-NPs) based urea biosensor is fabricated. ► NiO-NPs act as a suitable matrix due to its high catalytic activity along with the redox behaviour. ► Prepared biosensor of NiO nanoparticles provides an active surface for enzyme immobilisation. ► NiO-NPs catalyse the electrochemical oxidation of ammonia thus avoiding the use of second enzyme.