An Electrochemical Sensor for Determination of Vitamin B2 and B6 Based on AuNPs@PDA-RGO Modified Glassy Carbon Electrode

Insufficient or excessive consumption of Vitamin B2 (Vit B2) and Vitamin B6 (Vit B6) can cause harmful effects on human health conditions, it is therefore very important to control their content in supplements and food products. In this work, we report on a simple, sensitive and selective electrochemical sensor based on gold nanoparticles (AuNPs) on glassy carbon electrode (GCE) modified by a hybrid of polydopamine and reduced graphene (PDA-RGO), for determination of Vit B2 and Vit B6. The hybrid nanomaterial comprising PDA-RGO supported AuNPs is constructed through a one-step GCE modification process for electrochemical quantification of Vit B2 and Vit B6 in pharmaceutical formulations. Cyclic voltammetry result reveals that the effective response to Vit B2 and Vit B6 is according to the high electrical conductivity of AuNPs and the large surface area of PDA-RGO. Meanwhile, the sensor modified with a composite film shows a synergistic effect for catalyzing the analytes. Under optimized experimental conditions, these sensors show wide linear ranges of 0.02−60.0 μM and 0.03−600.0 μM, with the detection limits (LODs) of 0.0096 μM and 0.025 μM for Vit B2 and Vit B6, respectively. Additionally, the constructed sensors have been applied for quantifying Vit B2 and Vit B6 in pharmaceutical formulations. Such an effective electrochemical platform could be potentially applied for analyzing various components for therapeutic drug monitoring.