Supported liquid extraction (SLE) or solid-supported liquid extraction is a cartridge or well-plate based technique that is based on the principles of liquid-liquid extraction (LLE) but delivers some key advantages. SLE extraction uses an inert, high surface area support to serve as a stationary phase for interaction with aqueous samples. An aqueous sample is loaded onto a SLE cartridge or well and allowed time to adsorb to the surface of the solid support. Then, an immiscible organic solvent is passed over the inert material, eluting analytes of interest and leaving behind unwanted matrix like salts and polar interferences.
SLE cartridges differ from other cartridge-based extractions, like solid phase extraction (SPE), because the original sample is loaded onto the extraction bed and is not intended to flow through. Therefore, Agilent SLE cartridge and well plate formats are named according to the sample capacity, not bed mass. It is very important to choose the appropriate format based on your total loading sample volume.
Ideal for biological, food, and environmental samples, SLE extraction products enable rapid and reliable sample preparation. Because the interactions occur between a liquid and a solid, rather than two liquids, no emulsions are formed. This improves extraction efficiency compared to traditional liquid-liquid extractions. In addition, SLE extraction doesn’t require sample mixing or phase separation steps making it less time-consuming and labor intensive. By eliminating shaking, SLE is easy to automate.
For years, diatomaceous earth material has been used for SLE extractions. Since diatomaceous earth is mined, not manufactured, it is difficult to control particle size which can compromise results. Chem Elut S, a synthetic SLE extraction product, has a controlled particle size and delivers consistent flow and uniformity in every batch. This improves reproducibility by minimizing analyst-to-analyst and batch-to-batch variability.
Synthetic and diatomaceous earth sorbents are available in a variety of formats, including cartridges, 96-well plates, and VersaPlate formats. High-purity bulk sorbent is also available for your application needs.