Product News: Empore Solid Phase Extraction (SPE) Disks

31 Oct 2008

Empore™ Solid Phase Extraction (SPE) Disks provide an efficient alternative to liquid/liquid extraction for sample preparation. A proprietary process is used to entrap adsorbent particles into a matrix of PTFE to create a mechanically stable sorbent disk. The disks can be used for purification and concentration of analytes from aqueous samples. Empore SPE disks provide a sample prep solution for large volume aqueous samples. The disk format provides a large surface area for sorbent/sample contact. Fast flow rates and high throughput may be realized with use of an Empore solid phase extraction disk.

Empore extraction disks are available in a variety of sorbent chemistries to complement most analytical applications. Each sorbent exhibits unique properties of retention and selectivity for a particular analyte. The choice of which sorbent is best for a particular method will be influenced by the difference in chemical nature of the analyte from the sample matrix and the cleanliness of the resulting chromatography.

Product characteristics
The Empore SPE disks are available in 47 and 90 mm diameters. Empore 47 mm disks are efficient at processing relatively clean samples (samples with low suspended solids). Empore 90 mm disks are efficient at processing larger volume samples or samples with greater amounts of suspended solids.

Empore™ Filter Aid 400 and/or prefiltration may be helpful if the sample contains excessive particulates. If the sample contains a high concentration of suspended solids, allow the particles to settle (overnight if necessary). Tilting the sample container to allow particulates to settle on one side is suggested to aid in decanting only the liquid portion of the sample. Particulates can be added to the reservoir after most of the sample has been processed. The 90 mm disk is recommended for samples with excessive particulates or to reduce sample processing times.

Empore SPE disks are high density (HD) membranes composed of chromatographic particles averaging 10-12 μm in size. The high density membranes are designed for maximum extraction efficiency with minimal elution volumes for samples that have less matrix interference.

Empore™ Disk Technology

Empore™ Solid Phase Extraction Disks are produced by trapping sorbent particles within an inert matrix of polytetrafluoroethylene (PTFE). The resulting particle-loaded membrane yields a denser, more uniform extraction bed than can be achieved with traditional loosely packed SPE particles. The result is improved mass transfer kinetics with consistent performance in solid phase extraction methods.

The dense particle packing and uniform distribution within Empore disks offer outstanding sample preparation efficiency and reproducibility of results. Since the diffusion distance between particles is minimized, adsorption is more efficient, and extraction can be accomplished using low sorbent mass. The following performance gains can be realized:

• Reduced solvent volumes
• Small elution volumes
• Reduced time for eluate evaporation
• High throughput
• Channeling effects eliminated
• Excellent reproducibility/low CVs