Polymer films formed by the condensation of polyetheramines with P(CH2OH)(3) were synthesized and covalently coupled to the enzyme urease via the intrinsic reactive P-CH2OH hydroxyl groups. Urease activities of 1,140 U g(-1) and 5.5 U cm(-2) of polymer film were achieved without any additional coupling agents. Upon oxidation of the phosphorus, the intrinsic hydroxyl groups were inactivated and the resulting urease activities decreased by over 98%.