SPE Procedures for Extraction

Practically, when using solid phase extraction cartridges, it is first necessary to condition the packing material. This is done by rinsing the cartridge with a solvent, which will be chosen depending upon the type 

The analytes of interest will adsorb onto the packing material and the rest of the matrix solution with other components will pass through unretained OR 

Either way, the cartridge will be washed to ensure that all of the analytes of interest have passed through or that all of the other components have passed through. 

If the analytes of interest are adhered to the packing material, a solvent will be chosen that will effect their desorption in order to be collected and further analysed. The most commonly used method is to have the analytes of interest adsorbed onto the packing material, thus allowing the other components in the matrix to pass through unretained rather than the opposite scenario. This is because retaining the analytes generally results in a more efficient extraction. 

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