SOLID STATE DIFFERENTIAL PULSE VOLTAMMETRY (DPV) FROM SPOTS OF THIN LAYER CHROMATOGRAPHY (TLC): A NEW METHOD FOR ANALYSIS OF ANTIOXIDANT PHYTOACTIVES

SOLID STATE DIFFERENTIAL PULSE VOLTAMMETRY (DPV) FROM SPOTS OF THIN LAYER CHROMATOGRAPHY (TLC): A NEW METHOD FOR ANALYSIS OF ANTIOXIDANT PHYTOACTIVES. A new electroanalytical method coupling TLC-DPV in solid state was developed for quantitative determination of phytoantioxidants with medicinal purpose, e. g. rosmarinic acid (RA) in samples of phytopharmaceuticals, e. g. rosemary (Rosmarinus officinalis L.). The method showed to be feasible, presenting linearity in concentrations ranging from 0.694 x 10(-3) to 9.526 x 10(-3) mol L-1 (r = 0.9945), good sensibility, selectivity, reproducibility, repeatability, agility and affordable cost. The concentrations of RA in different extracts of rosemary ranged from 0.05 to 0.52 (% w/w), presenting high recovery levels when compared to HPLC.