MgNi2O3 nanoparticles as novel and versatile sensing material for non-enzymatic electrochemical sensing of glucose and conductometric determination of acetone

Abstract In the present work, we report the synthesis of pure MgNi2O3 and MgNi2-xAxO3 (A = Co or Zn; x = 2.5, 10, 25 wt%) nanoparticles by chemical precipitation method and its novel applications in the field of chemical sensors. Powder XRD, SEM, HRTEM and XPS characterization of the synthesized samples indicate formation of nearly phase pure undoped MgNi2O3 nanoparticles. At lower concentration (2.5 and 5 wt%), both Co and Zn loading yielded nearly phase pure Mg-123 samples. On the other hand, increase in dopant concentration, led to the segregation of small quantity of impurity phases Co3O4 and ZnO with the major phase being Mg-123. Results of electrical and electrochemical characterization studies indicated the influence of the dopants on the physical and chemical properties of MgNi2O3. Both the pure and doped MgNi2O3 nanoparticles have been applied for the fabrication of electrochemical and conductometric sensors for monitoring blood glucose and breath acetone respectively. Electrochemical tests indicated that the Co–MgNi2O3 is highly effective for the electrochemical detection of glucose. Under optimal conditions, glucose was monitored at concentration from 0.05 mM to 5 mM with sensitivity of 528.6 μA mM−1cm−2. With regard to breath acetone detection, the Zn–MgNi2O3 conductometric sensor showed the best performances with high response and low detection limit (0.5 ppm at SN = 3), fast response/recovery times of about 25 s and 250 s, respectively, at the operating temperature of 200 °C. The good electrochemical and gas sensing performances suggest that MgNi2O3 based nanomaterials can be considered as versatile and promising candidates for developing chemical sensors helpful in the management of acute complications of insulin dependent diabetes, such as hypoglycemia and ketoacidosis.