After selecting the appropriate adsorbent, we need to select the corresponding specification of the cartridge according to the volume of sample which needs to be determined. Because the mass of chemical compound which can be adsorbed by the adsorbent in SPE cartridge is limited, once the value exceeds it, the target component will not be reserved effectively. As a result, it is necessary to select the appropriate specification of SPE cartridge.
About the frequently asked question when using SPE cartridge, normally there are low recovery rate, poor reproducibility, bad purifying effect, and excessively fast or slow flow rate.
For the low recovery rate, we can use blank solvent and then recycle the loading solution and eluent. If the actual detect concentration exceeds 5% of the content, it means the target component is not well reserved on the filler. The possible causes are a lot. For example, the selection of the SPE cartridge is not appropriate, then we should choose the cartridge with stronger reservation capacity. Also, the loading solution or the eluent of the sample may have excessively strong eluting power, all we need to do is to decrease the power.