Figure 1.

Absorption spectra of: (A) Fe(III)-1,10-phenanthroline with ETD (6.0 μg mL^-1); (B) Fe(III)-2,2'-bipyridyl with ETD (6.0 μg mL^-1) and (C) Fe(III)- ferricyanide with ETD (6.0 μg mL^-1) versus reagent blanks for each method.