▎ 摘　　要

In this paper, we proposed an enzymatic urea sensor using urease-magnetic beads (MBs) modified graphene oxide (GO)/titanium dioxide (TiO2) composite layers. The urea sensor was prepared by screen-printing technology and radio frequency sputtering. TiO2 sensing film was deposited onto polyethylene terephthalate substrate, which serves as an efficient matrix for immobilization of urease. Preparation of GO/TiO2 films was completed after GO being deposited onto the TiO2 film. Moreover, the characterization and sensing properties of the urea sensor were performed by energy dispersive spectrometer, scanning electron microscope, atomic force microscopy, electrochemical impedance spectroscopy, and voltage-time measurement system. The results indicated that the GO/TiO2 urea sensor enhances its performance of average sensitivity, response time, and drift rate after modifying the sensing membrane though MBs.