On-line flame AAS determination of traces Cd(II) and Pb(II) in water samples using thiol-functionalized SBA-15 as solid phase extractant

Mesoporous thiol-functionalized SBA-15 was investigated as a microcolumn packed material for the on-line preconcentration of trace amounts of Pb(II) and Cd(II) in water samples before their flame AAS determination. The results indicated that the proposed method was tolerant to the coexistence ions, offered good linearity and the achievable enhancement factors were 34 for Pb(II) and 41 for Cd(II), and the detection limits (3σ) of 0.22 μg L−1 and 0.11 μg L−1 and the precision (RSD) for 11 replicate determination of 30 μg L−1 Pb(II) and 20 μg L−1Cd(II) were 0.4% and 0.3%, respectively.