Electrochemical oxidation of hyperforin on glassy carbon electrode and determination in herbal medicinal products

Hyperfolin, one of the active components of St. John's Wort and St. John's Wort extracts is oxidized on the glassy carbon electrode. Electrode process, type and reversibility were examined by means of cyclic voltammetry in various buffer systems (NaAc/HAc, Sorensen-phosphate buffer, borate buffer). A differential pulse voltammetric method was developed for the determination of hyperforin. In the concentration range from 1.0 wg/mL to 40.0 mug/mL there is a strong linearity between the concentration of hyperforin and peak height. The detection limit is 200 ng/mL. The differential pulse voltammetric method developed is used to determine hyperforin in herbal medicinal products.