extraction and determination of tannic acid in rosemary, anise, and cinnamon by reversal phase rp-hplc

a reversed-phase high-performance liquid chromatography method was used for quantitative tannic acid in (rosemary, anise and cinnamon) with isocratic mode. the column which has been used is c18 (250 mm×4.6 mm i.d.;5 µm) at room temperature, with a mobile phase composed of methanol /water which the best ratio for separation tannic acid was (90:10 v: v%) at (ph 6) and the optimum flow rate was 1.5 ml/min, the run time (5 min) at a detection wavelength 277 nm at room temperature. the linearity of calibration curve was (0.1-60 µg ml^-1). the value detection of limit and quantification were calculated to be 0.0037 and 0.0122 µg ml^-1 respectively. the precision and accuracy were (98.18-100.095%). the recoveries provided by the method were ranged between (-2.57-0.09).