Solid Phase Extraction (SPE)
Solid phase extraction is a chromatographic technique
used to prepare samples for subsequent analysis by removing interfering
substances that may be present. This is done either by retaining the substance
of interest and washing off everything else or by retaining the interfering
substances and eluting the product of interest.
Common SPE method uses a solid phase and a liquid phase to isolate one, or one type, of analyte from a solution. SPE is used to “clean up” the sample prior to chromatography for quantitation. One method is to load a solution onto the SPE phase, wash away undesired components, and then wash off the desired analytes with another solvent for collection.
In simplistic terms, pumping a sample through a disk or cartridge to trap organic analytes and then eluting the organic analytes from the solid sorbent with organic solvent is all there is to SPE methods. In practice; however, SPE methods are not quite this simplistic.
COMMON SPE APPLICATIONS:
• Pharmaceutical compounds and metabolites in biological fluids
• Drugs of abuse in biological fluids
• Environmental pollutants in drinking and waste water
• Pesticides and antibiotics in food/agricultural matrices
• Desalting of proteins and peptides
• Fractionation of lipids
• Water and fat soluble vitamins