Perchloric acid enhances sensitivity and reproducibility of the ferric-xylenol orange peroxide assay.

@article{Gay2002PerchloricAE,
  title={Perchloric acid enhances sensitivity and reproducibility of the ferric-xylenol orange peroxide assay.},
  author={Craig A Gay and Janusz M Gebicki},
  journal={Analytical biochemistry},
  year={2002},
  volume={304 1},
  pages={42-6}
}
The ferrous oxidation in xylenol orange (FOX) assay for hydroperoxides suffers from very narrow pH optimum in the range 1.7-1.8. Most published protocols recommend 25 mM sulfuric acid as the solvent, but this in practice does not ensure the maintenance of correct pH in the presence of materials such as samples of biological origin. Substitution of perchloric for the sulfuric acid resulted in a lowering of the optimum pH of the assay to 1.1, a decreased dependence of the absorbance of the ferric… CONTINUE READING