If your sample matrix needs some cleanup but does not require the intensive power of SPE or liquid-liquid extraction, we recommend comparing SLE to your current method. If your results have improved relative to using a dilute-and-shoot method, adopting SLE will be advantageous; but, if your samples still require additional cleanup, then SPE is recommended.
Evaluating whether SLE cleanup will work for your application is simple. If your analytes are neutral compounds, simply dilute in an aqueous solution and load them onto a Resprep SLE cartridge or 96-well plate. Wait five minutes, then elute in a nonpolar solvent. If you are analyzing acids or bases, pretreat the samples by adjusting the pH relative to the analytes’ pKa values. By changing the pH, you suppress the molecular charges, which increases partitioning into the extraction solvent.
Details on pretreatment pH adjustment and extraction solvent recommendations are available in our Resprep SLE instruction sheet (below).
