MWCNT-ruthenium oxide composite paste electrode as non-enzymatic glucose sensor

A non-enzymatic glucose sensor of multi-walled carbon nanotube–ruthenium oxide/composite paste electrode (MWCNT–RuO2/CPE) was developed. The electrode was characterized by using XRD, SEM, TEM and EIS. Meanwhile, cyclic voltammetry and amperometry were used to check on the performances of the MWCNT–RuO2/CPE towards glucose. The proposed electrode has displayed a synergistic effect of RuO2 and MWCNT on the electrocatalytic oxidation of glucose in 3 M NaOH. This was possible via the formation of transitions of two redox pairs, viz. Ru(VI)/Ru(IV) and Ru(VII)/Ru(VI). A linear range of 0.5–50 mM glucose and a limit of detection of 33 μM glucose (S/N=3) were observed. There was no significant interference observable from the traditional interferences, viz. ascorbic acid and uric acid. Indeed, results so obtained have indicated that the developed MWCNT–RuO2/CPE would pave the way for a better future to glucose sensor development as its fabrication was without the use of any enzyme.

► A simple non-enzymatic glucose sensor using MWCNT and RuO2 has been developed.
► The synergistic of RuO2 and MWCNT in the catalysis of glucose is observed.
► The transitions of redox pairs Ru(VI)/Ru(IV) and Ru(VII)/Ru(VI) are anticipated.
► The sensor exhibits good sensitivity, reproducibility, stability and reliability.
► In high pH medium it is not interfered by ascorbic and uric acids.