The Effect Of SPE Cartridge
When in trace analysis and preparation, it is a necessary process to enrich the target sample. For example, when analyzing PAHs in the water, we can add 1,000 mL sample of water into the SPE cartridge, with the PAHs reserved in the column.
Then, we can use 2 mL solvent to make elution. In this way, the PAHs is concentrated by 500 times, which means in the same detection condition, the method limit of detection of the analyte is only 1/500 of it before the process.
It can remove the impurity before instrumental analysis. On the one hand, this prevents the impurity from interfering the target sample and improves the sensitivity of the analysis. On the other hand, this also can avoid damage to the instrument from the impurity.
Some analysis instrument has a special requirement for the solvent which dissolves the analyte, it can be converted by SPE cartridge.
For example, when we use gas chromatography method to analyze the semi-volatile contaminant in the water if we make a direct injection, the water will affect the separation and damage the gas chromatography column, so we need to convert the solvent.