What are common causes of low recovery in capture and elute reverse-phase SPE methods? - WKB279613
Article number: 279613
ENVIRONMENT
- Oasis
- Sep-Pak
- Solid-phase extraction (SPE)
ANSWER
Potential causes of low recovery include:
- Sample matrix saturates the sorbent, not allowing all of the analyte or analytes to retain upon loading
- Analyte concentrations are too high compared with the amount of sorbent when loading the sample
- Incorrect SPE sorbent vs. the analyte (extremely polar analytes may not retain)
- Silica-based SPE sorbent not properly conditioned and equilibrated prior to loading
- Loading flow rate too high
- Incorrect pH used (if using mixed-mode Oasis packings)
- Too much organic solvent in the sample when loading
- Elution flow rate too high
ADDITIONAL INFORMATION
These are not all of the possible reasons why recoveries may be low in an SPE procedure.
Always collect the Load, Wash, and Elute fractions to check for the presence of the target analyte in any of those steps.
Also see the following, which includes a guidance on how to determine recovery: