Solid Phase Extraction (SPE) Supplies

SPE (Solid Phase Extraction) is a technique whereby a desired analyte, a cation or an anion, is concentrated and separated from a complex sample matrix onto a sorbent stationary phase. The interfering matrix, which is not retained, is effectively eliminated. As a result, the analyte can be analyzed at the best possible sensitivity range of the analytical technique, e.g. Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), without the risk of matrix interference.

In recent years another technique has become very popular, the technique of Matrix Component Retention. In this case, the sorbent is selected to retain unwanted components in the matrix and the analytes of interest are not retained. Again, because the potentially interfering components have been removed, better sensitivity is obtained in sample analysis. This technique is seen most often in the food industry.

In both cases, the sorbent is placed in cartridges or liquid chromatography columns that can hold varying quantities of unprocessed samples.

In general, the SPE method should follow 4 steps:

Step One: Conditioning - The sorbent is prepared for the sample.
Step Two: Retention - Filter the desired analyte(s) or the unwanted matrix components.
Step Three: Rinsing - Any possible undesired component that may have been absorbed on the sorbent is washed away.
Step Four: Elution - The selective desorption and collection of the analyte of interest from the cartridge or column.