Electrochemical Screening of Biomarkers in Chemotype Mexican Oregano Oils on Single‐Walled Carbon Nanotubes Screen‐Printed Electrodes

Abstract An electrochemical screening for the determination of total biomarkers (thymol and carvacrol) of Lippia graveolens using single‐walled carbon nanotubes screen‐printed electrodes (SWCNT‐SPEs) is proposed. The suitability of the approach was demonstrated using GC‐MS by the analysis of selected Mexican oregano essential oil chemotypes. The analytical performance was excellent in terms of inter‐droplet precision ( RSD ≤6 %), sensitivity and linearity. An electrochemical index of biomarkers is proposed for fast assessment of oregano quality using just 50 µL of the sample. The route here proposed constitutes a very convenient screening tool in decentralized analysis because of the simplicity, disposability and easy‐to‐use by non‐specialist user.