Removing photocatalyst particles by filtering the dispersions (dark and irradiated samples) through 0.2 µm polyamide syringe filters Placing ca. 30 µL of the obtained solutions on H2O2 test strips to obtain approximate H2O2 concentration Diluting the dark and irradiated samples to the adequate concentration range (based on test strip result) and performing colorimetric assay multiple colorimetric assays for H2O2 quantification and found that the assay based on N,N-Diethyl-p-phenylendiamin (DPD) and horseradish peroxidase (POD), orginally developed by , showed the lowest chemical cross sensitivity among the compared assays. This is likely because it is an enzymatic assay that benefits from the high selectivity of horseradish peroxidase towards H2O2. Purely chemical assays, such as those based on permanganate or vanadate, in contrast, also react with other oxidants/reductants.