Multianalyte electrochemical electrode for the determination of vitamins B2 and B6 in complex biosystem

Vitamin B 2 (VB 2 ) and vitamin B 6 (VB 6 ) as important vitamins for human health are mainly produced by industrial microorganism fermentation. Due to the complexity of fermentation system, there is a lack of an efficient, rapid, and convenient detection method in the fermentation production of these two vitamins. In this study, a multianalyte electrochemical electrode based on glassy carbon electrode (GCE) modified by nanoporous gold (NPG) film was developed. This is the first time that NPG realized the electrochemical detection of VB 2 and VB 6 in complex fermentation analysis. Under optimized conditions, the NPG-modified electrode exhibited good performance in VB 2 and VB 6 detection using differential pulse voltammetry (DPV). Two linear responses in wide concentration ranges for VB 2 from 5 to 250 μM and for VB 6 from 40 to 1000 μM were obtained with the limit of detection (LOD) of 0.1 μM and 0.4 μM as well as the high sensitivities of 178.02 μA mM −1 cm −2 and 43.14 μA mM −1 cm −2 , respectively. Furthermore, the detection of VB 2 and VB 6 in fermentation media was successfully achieved using the NPG-modified electrode with high sensitivity and strong anti-interference ability. Additionally, the NPG-modified electrode has a long life because of the metal characteristics of NPG. These above characteristics conformed that the multianalyte electrochemical electrode can realize the simultaneous detection of multiple substances such as substrates and products in a complex biosystem.