Ultrasensitive non-enzymatic electrochemical sensing of glucose in noninvasive samples using interconnected nanosheets-like NiMnO3 as a promising electrocatalyst

Abstract

Exploration of rapid, low-cost and more efficient glucose sensing systems has becoming a hot research topic to inspire researchers to discover new electrocatalyst with excellent electrocatalytic sensing performance. Herein, we used a simple hydrothermal method for the preparation of ilmenite-type of NiMnO3 (NMO) nanostructure. Results of surface morphological analysis reveals that the NMO appeared as interconnected ultrathin nanosheets-like (particle size=∼15 nm) structure, which helps to promote the diffusion of ions into the electrode surface, thus can get improved electrocatalysis. Further the successful formation of NMO was confirmed by X-ray diffraction and X-ray photoelectron microscopic measurements. After these surface analysis, as-synthesized NMO nanosheets were utilized as an electrocatalyst for enzymeless glucose sensing. As-fabricated sensor realized a broad dynamic range (0.00005–1.01 mM and 1.01–13.2 mM) and a lower detection limit as 14 nM with an excellent sensitivity of 7560.8 μA mM−1 cm-2. We also demonstrated the practicality of the developed sensor in determination of glucose in human blood serum, and some noninvasive samples such as saliva, and sweat samples and recoveries were reliable with the commercial glucose sensor. These results demonstrate that the present work could lead to a new generation of enzyme-less glucose sensor for clinical analysis and biochemical industries.