Colorimetric determination of trace orthophosphate in water by using C-functionalized silica coated magnetite.

In this study, we customized magnetic sorbents by functionalizing silica coated magnetite with octadecyl(C)silane (FeO@SiO@C). This sorbent was intended for the determination of trace orthophosphate (o-PO) in unpolluted freshwater samples. The o-PO was transformed to phosphomolybdenum blue (PMB), a known polyoxometalate ion.