Simultaneous determination of heavy metals in drinking waters and wines by methods: Ion pair-reversed phase high performance liquid chromatography and capillary zone electrophoresis

Simultaneous determination of metal ions in drinking waters and wines using ion paired reversed phase high performance liquid chromatography (IP−RPHPLC) and capillary zone electrophoresis (CZE) have been investigated. Co(II), Cu(II), Ni(II), Fe(II) and V(V) are analyzed as their Nitro-PAPS chelates. Reversed flow injection (rFI) is used for in-line complexation prior to their separation by IP-RPHPLC. The optimum mobile phase compositions, obtained from sequential simplex method by carried out on a C18 μBondapak column at a flow rate of 1.0 mL min-1 and detection at 570 nm, are 39.7% acetonitrile containing 5.5 mmol L-1 acetate buffer 5.0 containing 3.5 mmol L-1 tetrabutylammonium bromide (TBABr). Meanwhile, CZE condition is performed on an uncoated fused-silica capillary (30.0 cm effective length) with the electrolyte of 35 mmol L-1 borate buffer pH 10.0 in 10% acetonitrile and 0.04 mmol L-1 Nitro-PAPS, separation voltage of 15 kV and detection at 250 nm. The analytical performance of both methods are examined and discussed. The analysis time of IP-RPHPLC including in-line complexation by rFI and separation of five metals is 19 min whereas the analysis time of CZE is 7 min. A high risk of iron and copper contamination is found in all drinking water and wine samples studied. The results obtained from both proposed methods are comparable (t-test, 95% confidence limit).