The influence of SDS on the percentage of complexed ions adsolubilized was investigated by shaking 250 mL of a solution containing 50 lg of each ion through solid phase containing various
amounts of SDS, 0.8 g c-Al2O3; 15 mg 2-HIYPMI. In the absence of SDS, metal ions retained on 2-HIYPMI–alumina with efficiency lower than 60% for all ions. The retention of metal ions on hemimicelles, which have a hydrophobic surface, was clearly dependent on analyte complex polarity. Therefore, addition of SDS is necessary. At surfactant concentrations higher than about 3.75 mg/g alumina for 2-HIYPMI as chelating agents a decrease in the percentage of ions retained was observed as a result of the formation of micelles. The adsorption amount began to decrease when the SDS
added exceeded the above mentioned value. It can be explained