Renewable Column Separation for
Trace Element Assays
3.2.11.
SI-LOV renewable surface scheme for ultra-trace-metal preconcentration and matrix separation using Sephadex C-25 cation-exchange beads.
Sample loading. Sample solution is first aspirated into HC, followed by 20-μl suspension of Sephadex C-25 resin, which was entrapped in column C1, forming a microcolumn, trough which the following sample is being perfused. During this step, the carrier solution is continuously delivered to the ICP by the syringe pump IP.
Elution step. Beads are transferred to second column C2 and with the injection valve IV in the inject position, the retained analytes on the column are eluted and stored in storage coil SL. Finally, IV is switched to the load position and the content in SL is propelled into the ICP by the infusion pump which has been continuously operating.
LOV is mounted on top of a 6-port selection valve; SP, Syringe pump; HC, Holding coil; IV, Injection valve; IP, Infusion pump; SL, Sample loop; C1 and C2 are the columns.
