Glucose oxidase mimicking half–sandwich nickel(II) complexes of coumarin substituted N–heterocyclic carbenes as novel molecular electrocatalysts for ultrasensitive and selective determination of glucose

• Published in: Biosensors & bioelectronics Vol. 134; pp. 24 - 28
• Main Authors: Brinda, K.N., Achar, Gautam, Małecki, Jan Grzegorz, Budagumpi, Srinivasa, Nagaraju, D.H., Suvina, V., Balakrishna, R. Geetha
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.06.2019
• Subjects: Electro–oxidation; Half–sandwich Ni complex; Imidazolium salt; Non enzymatic glucose sensor; N–heterocyclic carbene; Half–sandwich Ni complex; Imidazolium salt; Electro–oxidation; Non enzymatic glucose sensor; N–heterocyclic carbene
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2019.03.057

Glucose oxidase mimicking nickel–based porous structures with organic anchors are developed as cheap and reliable electrochemical sensors for the quantitative detection of glucose. A series of sterically and electronically modulated, air– and moisture–stable half–sandwich nickel(II) NHC complexes were prepared and characterized. Under the optimized electrocatalytic conditions, the nickel complex immobilized glassy carbon electrodes (GCEs) displayed high sensitivity (0.663, 1.280, 1.990 and 0.182 μA/μM) towards glucose detection, which is much higher than that of 3D porous nickel networks. The limit of detection of modified GCEs is found in the range 1.56–2.09 μM with much wider linear sensing range, and having a catalytic rate constant of 0.273 × 103 M−1s−1. Finally, the selectivity of the modified GCEs towards glucose in presence of other blood constituents was also evaluated. •Four new sterically and electronically modulated NiNHC complexes were prepared.•These complexes can serve as anodic materials for glucose sensing applications.•Ni complex immobilized GCEs displayed high sensitivity and selectivity towards glucose detection.•The sensitivity was found to be 0.663, 1.280, 1.990 and 0.182 μA/μM, with the lower limit of detection.•The selectivity of the complex towards glucose in presence of other blood constituents was also evaluated.