All used reagents and solvents were of analytical reagent-grade. In order to prepare the poly(MIA) sorbent, glycidyl methacrylate (GMA), trimethylolpropane trimethacrylate (TMPTMA), 2,2′-azobisisobutyronitrile (AIBN), 1-methylimidazole (MIA) (Merck, Darmstadt, Germany), and acetonitrile (ACN) (Labscan, Dublin, Ireland) were used.
High-purity deionized water (DW) produced by the Millipore Milli-Q system (Millipore Corp., Milford, MA, USA) was used to prepare the aqueous solutions for the sorption/desorption experiments. The stock standard solutions of As were: 1000 mg/L As(III) (Fluka, Munich, Germany); 1000 mg/L As(V) (Merck, Darmstadt, Germany); 1000 mg/L monomethylarsonate (MMAs), prepared by dissolving disodium methylarsonate hexahydrate (CH3 AsO(ONa)2·6H2O) (Carlo Erba, Milan, Italy); 1000 mg/L dimethylarsinate (DMAs), prepared by dissolving of sodium cacodylate trihydrate ((CH3)2 As(O)ONa·3H2O) (Sigma Aldrich, St. Louis, MO, USA) in DW. The working standard solutions were prepared weekly and kept refrigerated at 4 °C.
AQUA-1, a drinking water certified reference material (CRM) from the National Research Council Canada (NRC) was used.
The pH of the sample solutions was adjusted with nitric acid or sodium hydroxide solution (Merck, Darmstadt, Germany). The elution solutions were prepared with acetic acid and hydrochloric acid (Merck, Darmstadt, Germany).
High-purity deionized water (DW) produced by the Millipore Milli-Q system (Millipore Corp., Milford, MA, USA) was used to prepare the aqueous solutions for the sorption/desorption experiments. The stock standard solutions of As were: 1000 mg/L As(III) (Fluka, Munich, Germany); 1000 mg/L As(V) (Merck, Darmstadt, Germany); 1000 mg/L monomethylarsonate (MMAs), prepared by dissolving disodium methylarsonate hexahydrate (CH3 AsO(ONa)2·6H2O) (Carlo Erba, Milan, Italy); 1000 mg/L dimethylarsinate (DMAs), prepared by dissolving of sodium cacodylate trihydrate ((CH3)2 As(O)ONa·3H2O) (Sigma Aldrich, St. Louis, MO, USA) in DW. The working standard solutions were prepared weekly and kept refrigerated at 4 °C.
AQUA-1, a drinking water certified reference material (CRM) from the National Research Council Canada (NRC) was used.
The pH of the sample solutions was adjusted with nitric acid or sodium hydroxide solution (Merck, Darmstadt, Germany). The elution solutions were prepared with acetic acid and hydrochloric acid (Merck, Darmstadt, Germany).