Effect of Urea on the Morphology of Co sub(3)O sub(4) Nanostructures and Their Application for Potentiometric Glucose Biosensor

• Published in: Electroanalysis (New York, N.Y.) N.Y.), 2014-08, Vol.26 (8), p.1773-1781
• Main Authors: Ibupoto, Zafar Hussain, Elhag, Sami, AlSalhi, MS, Nur, Omer, Willander, Magnus
• Format: Article
• Language: English
• Subjects: Biosensors; Enzymes; Glucose; Morphology; Nanostructure; Nanowires; Reproducibility; Ureas
• ISSN: 1040-0397; 1521-4109
• DOI: 10.1002/elan.201400116

In this study, an effect of different concentrations of urea on the morphology of cobalt oxide (Co sub(3)O sub(4)) nanostructures was investigated. The Co sub(3)O sub(4) nanostructures are fabricated on gold coated glass substrate by the hydrothermal method. The morphological and structural characterization was performed by scanning electron microscopy, and X-ray diffraction techniques. The Co sub(3)O sub(4) nanostructures exhibit morphology of flowers-like and have comprised on nanowires due to the increasing amount of urea. The nanostructures were highly dense on the substrate and possess a good crystalline quality. The Co sub(3)O sub(4) nanostructures were successfully used for the development of a sensitive glucose biosensor. The presented glucose biosensor detected a wide range of glucose concentrations from 110 super(-6)M to 110 super(-2)M with sensitivity of a -56.85mV/decade and indicated a fast response time of less than 10s. This performance could be attributed to the heterogeneous catalysis effect at glucose oxidase enzyme, nanoflowers, and nanowires interfaces, which have enhanced the electron transfer process on the electrode surface. Moreover, the reproducibility, repeatability, stability and selectivity were also investigated. All the obtained results indicate the potential use of the developed glucose sensor for monitoring of glucose concentrations at drugs, human serum and food industry related samples.