Development of screen-printed carbon electrodes modified with functionalized mesoporous silica nanoparticles: Application to voltammetric stripping determination of Pb(II) in non-pretreated natural waters

A screen-printed carbon electrode modified with functionalized mesoporous silica nanoparticles (MTTZ-MSU-2) was developed and evaluated for reliable quantification of trace Pb(II) ions by anodic stripping square wave voltammetry in non-pretreated natural waters. The optimal operating conditions were 5 min preconcentration time and 120 s electrolysis time in HCl 0.2 M. The electrode displayed excellent linear behavior in the concentration range examined (1-30 μg L⁻¹) with a limit of detection of 0.1 μg L⁻¹. The screen-printed carbon modified electrode has long service time and good single and inter-electrode reproducibility. Applicability to spiked drinking water, river water and groundwater was demonstrated without any sample pre-treatment (recoveries between 97% and 106%, RSD 4-7%). On the basis of the present data, mercury-free screen-printed electrodes modified with functionalized mesoporous silicas have the potential to become the next-generation analyzers for decentralized heavy metal monitoring in environmental samples.