SPE Cartridges

Rule I:

The properties of solid phase packing in SPE cartridges should be match to target compounds.

Rule II:

Take the advantage of differences between analytes of interest and interferences

Rule III:

Consider nature of SPE sample matrices, characteristics of analytes and solubility of used solvents

Users can select RayCure SPE columns depending on properties of desired analytes and sample matrices as following selection guides.

Based on nature of SPE sample matrices

SPE is a conventional and efficient extraction technique, it uses the affinity of solutes dissolved or suspended in mobile phase for stationary phase to separate desired compounds from a mixture. And there are two solid phase extraction mechanisms to obtain target analytes from complex samples, to retain desired compounds in stationary phase or retain impurities in solid phase. Depending on the difference of two mechanisms, SPE procedures could be a bit various. 

When sample portion passes through SPE column, undesired impurities are discarded with mobile phase, target compounds are retained in stationary phase, then rinse stationary phase with eluents to collect target compounds. It is the most commonly used purification mechanism of solid phase extraction. 

In the opposite, to retain impurities in stationary phase, target compounds and few impurities are collected in mobile phase when sample portion passes through SPE column. Rinse the stationary phase which impurities is retained with solvents to obtain rest of retained target compounds. This mechanism is mostly used to eliminate fat-soluble impurities of ion analysis and analysis of multiple pesticides in fruits and vegetables.