Integrated retention/spectrophotometric detection in flow-injection analysis : Determination of Iron in Water and Wine

An integrated retention/spectrophotometric method is proposed for the determination of iron based on the Fe (III)-thiocyanate complex. The method has good selectivity, with a determination limit of 10 ng ml^?1 and a linear range of 10–400 ng ml^?1. Different types of measurements (peak height, absorbance increment, tangent curve) are shown to have their particular advantages. The method is applied to the determination of iron in natural water and wine, with an average recovery of 100.3% and 98.8% and an average deviation of the recovery of 2.5% and 1.6%, respectively.