A new hydrophilic frit for solid phase extraction (SPE) manufactured from polyethylene which includes long chain olefinic oligomers that are terminated with a hydrophilic group is now available
The weakly ionic group has an extremely low affinity for cations as it is present in picomolar properties.
In ion-exchange separations, the group can be considered as essentially non-existent when compared to the SPE adsorbent.
The hydrophilicity of the frit is long lived due to the nature of the bonding of the oligomeric group and can be considered as permanent for most applications.
No solvent pre-treatment of the SPE cartridge is required and the user can obtain gravity flow of aqueous samples.
An additional benefit is that flow through the cartridge can be obtained with pure water, and does not require the use of a pre-solvent such as methanol, ethanol or iso-propanol before the water wash is used.
The frit is cut using a rotary cutter to make certain that the edges of the frit are uniform and of lower porosity than the bulk of the frit.
This ensures a perfect fit of the frit in the cartridge and the loss of packing materials in almost non-existent.
In contrast, most SPE frits are cut using a die; this may lead to loss of packing material as a perfect fit is not obtained.
