2 Solid Phase Extraction (Exhaustive Extraction)Analyte either adsorps or absorbs to a solid supportAdvantagesLarge concentrations possibleLimited use of solventsVery effective clean-up techniqueDisadvantagesTime consumingPrecision can be difficultExpensive
4 Solid Phase Extraction - Air (Exhaustive Extraction)SorbentsXADHigh surface area ( m2/g)PUFPolyurethane foamTENAXModerate surface area (19-30 m2/g)Thermally stable, appropriate for thermal desorption
5 Solid Phase Extraction - Water (Exhaustive Extraction)SorbentEnvironmentPumpWaterWater sampleSorbentLabVacuum manifold
6 Solid Phase Extraction - Water (Exhaustive Extraction)SorbentsSilica-based stationary phaseSimilar to LC phase - C18 most commonLimited pH stability‘Finicky’ to handlePolymericStable from pH 1-14Not ‘finicky’
7 Silica-based SPE cartridges Procedure:1. Condition cartridge2. Load sample3. Wash co-extractables4. Elute analytes of interestSiC18 tailsTails ‘solvate’ during step 1 (conditioning), will collapse if the cartridge goes dry. Extraction is ruined
8 Polymeric SPE cartridges Procedure:1. Condition cartridge2. Load sample3. Wash co-extractables4. Elute analytes of interestNo tails to ‘solvate’, and so extraction can continue even if cartridge goes dry
9 Polymeric SPE cartridges Because of the wide pH stability are able to use pH to control extraction. Very selective and effective extraction technique.
10 Solid Phase Micro Extraction (SPME) Only equilibrium extraction method described here.Often used to observed volatile materials in a laboratory setting.N2 inSorbentSample