The solid phase extraction column (SPE column for short) is a sample pretreatment device developed from a chromatography column for extraction, separation and concentration. It is mainly used in sample pretreatment of target compounds in various food, agricultural and animal products, environmental samples and biological samples. Solid phase extraction technology is widely used in many national standards (IOS) and industry analysis standards.
Principle of solid phase extraction
SPE technology is based on the theory of liquid-solid chromatography and uses selective adsorption and selective elution for sample enrichment, - separation, and purification is a physical extraction process that includes liquid phase and solid phase; it can also be viewed as a simple chromatographic process.
SPE is the separation principle of liquid chromatography using selective adsorptiontion and selective elution. The most commonly used method is to pass the liquid sample solution through the adsorbent, retain the test substance in it, then use a suitable strength solvent to wash off the impurities, and then use a small amount of solvent to quickly elute the test substance , to achieve the purpose of rapid separation, purification and concentration.
It can also selectively adsorb interfering impurities and emit the measured substance; or simultaneously adsorb impurities and the measured substance, and then use an appropriate solvent to selectively elute the measured substance.
The sieveless SPE column is a new type of integrated SPE column.
Solid phase extraction column advantages:
1. No sieve plate, perfectly avoiding the “non-specific adsorption” caused by the sieve Pbar.
2. The putty has good stability and performance, and there are no common problems such as loose putty.
3. The integrated design of the overall packaging effectively avoids the trench effect.
4. Fillers with a particle size as small as 8-10 μm can be selected, greatly improving the separation efficiency and sample loading capacity.
The capacity of the solid phase extraction column refers to the adsorption capacity of the packing of the solid phase extraction column. For silica-based solid phase extraction columns, the capacity is generally 1-5 mg/100 mg, i.e. H. the column capacity is 1–5% of the packing mass. The capacity of the bound silica gel ion exchange adsorbent filler is expressed in meq/g, i.e. H. the capacity per gram of filler is X milligram equivalent. The capacity of this type of packaging is usually 0.5 to 1.5 meq/g.