Quantofix Phosphate test strips and reagent for the semi-quantitative determination of ortho-phosphte (PO 4 3-) in solutions

Quantofix Phosphate test strips has a gradation of scale: 0-3-10-25-50-100 mg/L PO43- white to blue-green.

Only Ortho-phosphate is determined. Other phosphates, such as poly-, pyro-, and metaphosphates, have to be decomposed for the determination of total phosphates. Silica (SiO 2) contents above 10 mg/L react in the same way giving a blue coloration. Larger amounts of sulphide ions (S 2) cause a brown color of the test field, smaller concentrations cause low results. The following ions do not interfere: 1000 mg/L Ag +, Al 3+, Cd 2+, Co 2+, Cr 3+, Mg 2+, Mn 2+, NH 4+, Ni 2+, Zn 2+, Cl-, F -, NO 3-, SO 4 2-, citrate, oxalate, tartrate, <500 mg/L Ca 2+, < 250 mg/L Pb 2+, <50 mg/L Cu 2+ <25 mg/L Fe 3+, 5 mg/L Fe 2+, <2 mg/L NO 2 -.