Fluorometric determination of peroxides in an HPLC system

Hemin was used to substitute for horseradish peroxidase (HRP) as catalyst w ith p-hydroxyphenyl acetic acid (PHPAA) as substrate for post-column detect ion of H2O2 and methyl hydroperoxide (CH3OOH, MHP) in an HPLC system. In a hemin-catalyzed system, post-column reaction and fluorescence measurement c an both be conducted optimally at a pH of similar to 10.5. Hydroxymethyl hy droperoxide (HOCH2OOH, HMHP) and bis(hydroxymethyl) peroxide (HOCH2OOCH2OH, BMHP) will rapidly be converted to H2O2 in alkaline solution and can also be detected. The HPLC system is optimized for the analysis of H2O2 and MHP. Reproducibilities are better than 5% for H2O2 and MHP. The detection limit s in aqueous solution are 9 nM for H2O2 and 200 nM for MHP.