A novel nanosensor based on Pt:Co nanoalloy ionic liquid carbon paste electrode for voltammetric determination of vitamin B9 in food samples

•Synthesis and application of Pt:CO nanoalloy as a sensor for vitamin B9 analysis.•The electrooxidation of vitamin B9 was studied by ionic liquid/Pt:CO paste electrode.•The sensor was used for determination of vitamin B9in food samples.

In this work we describe a novel nanoalloy (Pt:Co) room temperature ionic liquid (RTIL) modified carbon paste electrode as a high sensitive sensor for voltammetric determination of vitamin B9 in food samples. The sensor exhibits an enhanced effectiveness for the electro-oxidation of vitamin B9 in aqueous solution. The oxidation peak potential for this matter at a surface of the ionic liquid (n-hexyl-3-methylimidazolium hexafluoro phosphate) Pt:Co carbon paste electrode (Pt:Co/IL/CPE) appeared at 685 mV that was about 110 mV lower than the oxidation peak potential at the surface of the traditional carbon paste electrode (CPE) under similar condition. The mechanism of the electro-oxidation process on the surface of the modified electrode was analyzed. Square wave voltammetry (SWV) was applied as a very sensitive electrochemical method for the determination of sub-micro-molar amounts of vitamin B9. The linear response range and detection limit were found to be 1.0 × 10−7 to 5.0 × 10−4 M and 4.0 × 10−8 M, respectively. The prepared modified electrode shows several advantages such as simple preparation method, high stability, high sensitivity, and excellent catalytic activity, long-term stability and remarkable voltammetric reproducibility for eletrooxidation of vitamin B9. The proposed sensor was successfully applied for the determination of vitamin B9 in food samples.