Sensitive reversed-phase liquid chromatographic determination of hydrogen peroxide and glucose based on ternary vanadium(V)-hydrogen peroxide-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol system Original Research Article

The ternary titanium(IV), vanadium(V) and molybdenum(VI) complexes with H2O2 and 5-Br-PADAP were investigated by spectrophotometry (Vis) and chromatography (LC). Occurrence of two different ternary titanium(IV) complexes with hydrogen peroxide and 5-Br-PADAP (limited by concentration of methanol in the sample) was established. Stability of Ti(IV) and V(V) ternary complexes under spectrophotometric and chromatographic conditions was discussed. Two liquid chromatographic methods for the determination of hydrogen peroxide based on the Ti(IV) and V(V) ternary complexes were developed. Calibration curves are linear within wide ranges of hydrogen peroxide concentration: 0.02–5.00 and 0.15–5.00 μmol l−1 with detection limits 0.016 and 0.150 μmol l−1 for vanadium(V) and titanium(IV) systems, respectively. The method based on vanadium(V) system was used for the determination of H2O2 traces in rainwater, generated in water subjected to sonication and on the surface of the plant leaf (Plantago lanceolata L.), as well as for indirect determination of glucose in a human serum.