Rapid glucose detection using graphene oxide modified foam nickel electrode with optimized basic solution

Abstract

Sugar is one of the important content within food. The classic sugar determination method is precise but needs fuzzy operation, which indicating the high cost. With the rapid development of functional materials in the past decades, a glucose sensor with small size is supposed utilizing the popular nano-sized materials. In this paper, glucose quantitative detecting system was proposed using graphene oxide (GO) modified foam nickel electrode, Pt electrode, and Ag/AgCl electrode. Na2CO3, NaOH, and NH3 in different concentrations were utilized to explore the optimized basic solution. Cyclic voltammetry (CV) and current-time (i-t) scanning were accepted to study the linear relationship between glucose concentration and current density. Results demonstrated that the optimized basic solution content was an equal volume of Na2CO3 and NaOH according to sensor’s sensitivity and responding current density. However, the responding sensitivity of optimized basic solution became weaker than pure NaOH basic solution. In order to increase chemical sensitivity of the electrode, GO was used to modify foam nickel electrode. Results indicated that the responding current was effectively increased. The responses presented good linear relationship with glucose concentration (I = 0.226 c + 0.8289, R2 = 0.9998). The detecting limit was 13.3 μmol/L. The presence of GO in foam nickel structure tremendously increased the detecting sensitivity. The decrease of NaOH volume in basic solution proposed a green way for this technique in sugar rapid analysis, glucose analysis in blood.

Keywords

• nickel foam
• graphene oxide
• glucose sensor
• quantitative analysis
• optimization