A new method for the determination of trans-resveratrol employing voltammetry (direct current voltammetry (DCV), differential pulse voltammetry (DPV), adsorptive stripping differential pulse voltammetry (AdSDPV)) and flow injection analysis (FIA) with electrochemical detection (ED) at a carbon fiber rod electrode (CFRE) was developed and compared with the voltammetric determination using carbon paste electrode (CPE) and FIA with spectrophotometric detection (SPD). Optimum conditions were found to be Britton-Robinson (BR) buffer pH 2 - methanol (1:1, v/v) for voltammetry (except for AdSDPV where BR buffer pH 10 - methanol mixture, 95:5, v/v was used), and BR buffer pH 10 - methanol (1:1, v/v) medium with the detection potential + 1.0 V or wavelength 306 nm for FIA.
Practical applicability of the methods was tested on the determination of trans-resveratrol in Evelor pastilles. The results were in agreement with the results obtained using CPE and spectrophotometric detection and also with the content declared by the manufacturer.