Preparation of perovskite-type composite oxide LaNi0.5Ti0.503-NiFe204 and its application in glucose biosensor

摘要

A novel nanostructured perovskite-type composite oxide LaNi 0.5Tio.503-NiFe204 (LNT-NFO) was synthesized by sol-gel method and characterized by X-ray diffractometer (XRD) and transmission electron microscopy (TEM). Amperometric glucose biosensors based on the carbon paste electrode (CPE) were constructed by immobilizing glucose oxidase (GOD) with LNT-NFO and the experimental conditions such as the amount of GOD, pH value, and applied potential were investigated. Under the optimum conditions, the electrochemical performances of the LNT-NFO with different ratios of LNT-NFO (10:1, 20:1, 30:1) modified CPE have been researched on the oxidation of glucose. The results show that LNT-NFO (20:1) can immobilize GOD more effectively. The biosensor based on LNT-NFO/CS/GOD modified CPE exhibits good reproducibility, stability and selectivity in glucose determination with linear signal-to-glucose concentration range of 0.5-10 mM and a detection limit (S/N = 3) of 0.04 mM.