JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY, cilt.24, sa.5, ss.856-866, 2013 (SCI-Expanded)
The poly(N, N'-dipropionitrile methacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propanesulfonic acid) resin was synthesized as a new chelating adsorbent for speciation of chromium in water and food samples by flame atomic absorption spectrometry (FAAS). The resin was characterized using Fourier transform infrared spectroscopy (FTIR), elemental analysis, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Effects of pH, concentration of elution solution, sample flow rate, sample volume and interfering ions on the recovery of Cr(III) were investigated. The sorption capacity of the resin was found to be 12.1 mg g(-1) for Cr(III). A high preconcentration factor (150) and low relative standard deviation (2.0%, n = 10) were obtained. The limit of detection of the method was 1.11 mu g L-1. The method validation was performed by analyzing certified standard reference materials (TMDA-70 lake water and SRM 1568a rice flour) and spiked water and food samples. The developed method was applied to the determination of the chromium in various water and food samples.