Spectrophotometric determination of iron with zephiramine

Abstract

Zephiramine reacts with iron thiocyanate complex ions to form a reddish-brown precipitate. The precipitate is extracted with chloroform, and the extract is stable for at least 2days after extraction, and shows an absorption maximum at 470mμ. The absorbance of the extract is invariable in the acidic region (pH1.20.2). Beer's law holds for the chloroform extract when iron-thiocyanate-zephiramine was extracted in 10.0ml chloroform from 25.0ml sample solution containing 0.5×10-6M 5.0×10-6M Fe(III). Metal ions, except for copper and bismuth, do not interfere with the determination.