Pinar, Pinar TalayYardim, YavuzSenturk, Zuhre2025-05-102025-05-1020200026-92471434-447510.1007/s00706-020-02556-y2-s2.0-85079451020https://doi.org/10.1007/s00706-020-02556-yhttps://hdl.handle.net/20.500.14720/5951Senturk, Zuhre/0000-0002-0356-9345; Yardim, Yavuz/0000-0002-9587-096XIn this study, a cheap, rapid, simple, and modification-free electroanalytical methodology based on the disposable pencil graphite electrode is described for the quantification of higenamine (isoquinoline-type alkaloid having three phenolic OHs). At first, the electrochemical oxidation of higenamine was investigated in aqueous solutions by cyclic voltammetry. The electrode process is pH-dependent and controlled by a mixture of diffusion and adsorption processes. Higenamine yielded two well-separated oxidation steps in acidic, neutral, and alkaline media by using square-wave voltammetry. By using the first oxidation peak due to its higher sensitivity, there was an excellent correlation between oxidation peak current at + 0.44 V and higenamine concentration (as hydrochloride salt) in the range of 0.05 to 2.0 mu g cm(-3) (1.63 x 10(-7)-6.5 x 10(-6) mol dm(-3)), with a detection limit of 0.014 mu g cm(-3) (4.55 x 10(-8) mol dm(-3)) in Britton-Robinson buffer at pH 4.0. As an example, the developed approach can be used for the quantification of higenamine in the commercial dietary supplement formulations. Graphic abstracteninfo:eu-repo/semantics/closedAccessHigenaminePencil Graphite ElectrodeSquare-Wave VoltammetryDietary SupplementsArticle1513Q3Q2301307WOS:000513059000001