In this study,reactive RF sputtered
nanoporous ZnO thin film with excellent uniformity of thickness has been used for fabrication of the electro chemical urea
biosensor via immobilization of Urs. Fabricated biosensor showed high sensitivity,low detection limit,broad dynamic range,fast
response time,high stability and longterm reproduc ibility by retaining enzyme activity due to the suitable immobilization of
Urs in nanoporous ZnO thin film.