Application of derivative voltammetry in the quantitative determination of alloxan at single-walled carbon nanotubes modified electrode

Abstract

Alloxan is a glucose analogue produced by the oxidation of uric acid and assumes physiological significance owing to its toxicity and diabetes inducing nature. Foods tainted with alloxan are considered as a leading cause of diabetes. Hence, real time quantification of alloxan is mandatory to estimate the diabetogenic risk of food samples. Electrochemical activity of alloxan at various carbon nanomaterials has been used for the quantitative determination of alloxan in neutral and acid media. This method has made use of derivative technique that does not require further instrumentation but has remarkably improved the sensitivity. Alloxan has exhibited the highest electrochemical activity at single-walled carbon nanotubes among the investigated carbon nanomaterials. The redox activity of alloxan has disappeared in the conventional voltammogram at a concentration of 3 × 10−6 M, whereas, prominent peaks have been observed well below 3 × 10−7 M in derivative voltammograms. Linear calibration graphs have been constructed in the concentration range between 3 × 10−3 and 3 × 10−7 M both in neutral and acid media. The detection limits of alloxan in neutral and acid media are 5 × 10−8 and 1 × 10−7 M respectively.