Common in pool filters and gardens, diatomaceous earth has many everyday uses. However, in the laboratory, it is utilized for its unique extraction qualities as the solid support in Supported Liquid Extraction (SLE). To understand the benefits of using SLE compared to Liquid-Liquid Extraction (LLE), read our article that addresses, the common misconceptions surrounding LLE.
We offer two types of SLE sorbents to make sure that you have a solution to whatever you may encounter in the lab. Novum™—a novel, synthetic SLE sorbent, is optimal for analytes that are more soluble in ethyl acetate and is an excellent option for those who need increased consistency and reliability. Strata®DE—a traditional diatomaceous earth sorbent—is a guaranteed cost-effective alternative to other SLE products on the market.
SLE—also known as Solid Liquid Extraction—cleans up matrix interferences by initiating the partitioning of a water immiscible extraction. In our Strata DE SLE product, the sorbent is made of diatomaceous earth (DE), which is mined from fossilized diatoms. Let’s face it, the earth is unpredictable, so DE can vary in sorbent characteristics due to the location where it was mined. This demonstrates that not all DE is created equal and QC tests (hint, we have many!) must be rigorous to ensure a reliable SLE product that provides accurate results every time.
To run an SLE method, the sample must be diluted at least 1:1 in aqueous conditions before it is loaded onto the SLE sorbent to guarantee an accurate extraction. Loading volumes can vary by SLE product, and since we have extensively researched our DE product, we recommend loading about 300 µL on our 400 µL plate to ensure that full extraction capabilities are reached. This can vary in different SLE protocols and is an extremely important part of our QC tests so all extractions are accurate and reliable. We recommend this safe precaution to prevent overloading, which can compromise the cleanliness of your extraction.
In addition to the variability in diatomaceous earth, the extraction solvent can play a significant role in the effectiveness and consistency of analyte recovery. You will want to choose a solvent that not only provides accurate recoveries but also leaves the unwelcomed interferences behind on the sorbent to minimize the possibility of ion suppression and column fouling due to phospholipids or salts that may elute into your final sample. For the Strata DE product, we have many applications that can assist you in understanding if Strata DE is the right SLE product for you.
Visit www.phenomenex.com/stratade to learn more.