MOF-Derived Spinel NiCo2O4 Hollow Nanocages for the Construction of Non-enzymatic Electrochemical Glucose Sensor

Non-enzymatic glucose sensor is greatly expected to take over its enzymatic counterpart in the future. In this paper, we reported on a facile strategy to construct a non-enzymatic glucose sensor by use of NiCo2O4 hollow nanocages (NiCo2O4 HNCs) as catalyst, which was derived from Co-based zeolite imidazole frame (ZIF-67). The NiCo2O4 HNCs modified glassy carbon electrode (NiCo2O4 HNCs/GCE), the key component of the glucose sensor, showed highly electrochemical catalytic activity towards the oxidation of glucose in alkaline media. As a result, the proposed non-enzymatic glucose sensor afforded excellent analytical performances assessed with the aid of cyclic voltammetry and amperometry (i-t). A wide linear range spanning from 0.18 mu M to 5.1 mM was achieved at the NiCo2O4 HNCs/GCE with a high sensitivity of 1306 mu A mM(-1) cm(-2) and a fast response time of 1 s. The calculated limit of detection (LOD) of the sensor was as low as 27 nM (S/N=3). Furthermore, it was demonstrated that the non-enzymatic glucose sensor showed considerable anti-interference ability and excellent stability. The practical application of the sensor was also evaluated by determination of glucose levels in real serum samples.