The effect of supporting electrolyte for the simultaneous determination of vitamin B2, vitamin B6, and vitamin C using a modification-free screen-printed carbon electrode
To open a new choice and to replace the complicated steps of a modified electrode, this research reported on the systematic investigation of the type of supporting electrolyte that affected to the electrochemical behavior of vitamin B2 (VB2), vitamin B6 (VB6), and vitamin C (VC) using a common screen-printed carbon electrode (SPCE) to obtain the simultaneous detection. The role of various well-known supporting electrolytes, including Britton-Robinson buffer solution (BRBS), acetate buffer solution (ABS), and phosphate buffer solution (PBS), on the electrochemical oxidation of VB2, VB6, and VC were carefully accomplished by square wave voltammetry (SWV). From this successive investigation based on the ionic conductivity of species containing in a supporting electrolyte, PBS at pH 3.5 was selected as a suitable supporting electrolyte for the simultaneous detection of VB2, VB6, and VC. Under the optimized conditions, the simultaneous detection of VB2, VB6, and VC provided satisfactory sensitivity, selectivity, and reproducibility despite using a common electrode. To demonstrate the practicality and reliability of the proposed analytical procedure, the simultaneous detection of VB2, VB6, and VC was performed in mixed vegetable and fruit juice and urine sample by SWV and the results were compared with chromatographic detection. Therefore, this finding is simple and could be a new alternative way for the simultaneous determination of VB2, VB6, and VC in practical applications.