Basic Steps For SPE Columns Operation
Solid phase extraction (SPE) is used to reduce sample matrix interference and improve detection sensitivity. The separation selectivity of the solid phase depends on the retention strength of the components that can be retained, so the selection of the solid phase will depend on the shape of the analyte and the sample solvent.
Composition of SPE
1. The column tube: made of serum-grade polypropylene in the shape of a syringe.
2. Sintered mat: fixation and filtration.
3. Fixed phase: commonly bonded silica gel materials.
Basic steps of SPE columns
1. Select extraction tube
2. Pretreatment of the extraction tube
3. Add samples
4. Rinse the filler
5. Elution of compounds
SPE can be used for sample pretreatment of gas chromatography, liquid chromatography, infrared spectroscopy, mass spectrometry, NMR, UV, and AAS.
The solvent strength of the positive solid phase increased with increasing polarity. The solvent strength of the inverse-phase solid phase increased with the increase of non-polarity. Common solvents are water, methanol, isopropyl alcohol, and acetonitrile, and sometimes acetone and dichloromethane.
In general, SPE improves the technique of sample preparation.