Polyurethane foam functionalized with phenylfluorone for online preconcentration and determination of copper and cadmium in water samples by flame atomic absorption spectrometry

In this work, a polyurethane foam (PUF) functionalized with phenylfluorone (PUF-PF) was packed in a minicolumn and used as an on-line preconcentration system for cadmium and copper determination in water samples. The experimental conditions (both chemical and physical) were optimized to achieve the highest sensitivity. A study of possible ion interference on the retention of cadmium and copper was also performed. The enrichment factors obtained were 14 and 16 for copper and cadmium, respectively, using a preconcentration time of 1 min. The proposed system allowed the determination of metals with limits of detection (3σ) of 0.8 and 0.3 μg L− 1 for Cu(II) and Cd(II), respectively. The precision of the procedures was also calculated as 7.6% for Cu(II) (at 25 μg L− 1) and 4.0% for Cd(II) (at 10 μg L− 1). The limits of quantification obtained were 2.6 and 0.8 μg L− 1 for Cu(II) and Cd(II), respectively. Cadmium and copper contents in water samples (from rivers and swimming pools) were determined by applying the proposed procedure. In these samples, recovery tests were conducted in order to evaluate the accuracy of the method; the recovery percentages varied between 83 and 109%.