Rapid Nanomolar Detection of Guaiacol from its Precursors Using a Core‐shell Reversed‐phase Column Coupled with a Boron‐doped Diamond Electrode

The electrooxidation mechanisms of guaiacol (2‐methoxyphenol), a food and beverage spoilage metabolite, and its precursors; vanillic acid (VA), vanillin, and ferulic acid (FA) were investigated by cyclic voltammetry (CV) with a boron‐doped diamond (BDD) electrode. Reversed‐phase liquid chromatography (RPLC) together with a BDD electrode poised at +1.6 V vs. Pd/H2, was optimized for their sensitive detection. The separation was achieved in 60 s with a core‐shell column (HALO C18). The detection limits of these analytes ranged from 10–30 nM. The method was applicable for the analysis of guaiacol and its precursors from a popular commercial drink.