Spectrophotometric assay of iron (II)‎ in pharmaceutical formulation using alizarin red sulphonate reagent

Abstract EN

A rapid, sensitive and simple spectrophotometric method was developed for the determination of iron (II).

The method was based on the reaction of iron (II) with alizarin red sulphonate reagent to form a brown chelating complex in an aqueous solution.

The absorbance of the chelating complex was measured at 566 nm with a molar absorptivity of 7.8 x 103 l.mol-1.cm-1.

The chelating complex conforms to Beer's law over the range (0.5-5) g.ml-1.

the average recovery % was 100.06 % and precision (RSD) was found to be less than 1 %.

The method was successfully employed for assay of iron (II) in pharmaceutical formulations (tablets and capsules).

The results have been compared with British pharmacopoeia method.