Novum™ Simplified Liquid Extraction (SLE) Method Development – A Corticosteroid Case Study

Introduction

Simplified Liquid Extraction (SLE), also known as Supported Liquid Extraction, has been developed as an alternative sample preparation method to liquid-liquid extraction (LLE) to remedy some of the drawbacks including the formation of emulsions, difficulty in automating, and the use of large amounts of hazardous solvents. The particle size of the solid support in an SLE material mimics the shaking event in a LLE workflow and creates micrometer scale containers for aqueous sample. By increasing the surface area and reducing the diffusion distances, one promotes a rapid and efficient extraction that negates the necessity of manual phase separation. Novum, a synthetic SLE sorbent, yields results that are identical in most cases to contemporary diatomaceous earth SLE products, but is not restricted by limitations that are associated with natural resources such as availability and variation in composition. In this technical note we will investigate a case study using a corticosteroid panel to demonstrate that Novum is capable of achieving equivalent recoveries, while also offering the analyst the added option of additional clean up and phospholipid removal that cannot be achieved on traditional diatomaceous earth SLE products. We also offer general tips that can help with the method development process for other compounds of interest.