Solid Phase Extraction Frits and Filters - Frits are friction fitted within the cartridge to retain the sorbent, and also to perform a variety of filtration functions. Applied Separations’ porous plastic frits are naturally hydrophobic, but aqueous solutions can be forced through under pressure. If gravity flow of an aqueous solution is desired, then select a specially treated polyethylene hydrophilic frit... xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Solid Phase Extraction Frits and Filters
Polyethylene hydrophobic frits are the standard and are used in most commercial SPE products. They are also used with non-aqueous solutions such as solvents, alcohols, acids, bases, halogenated and aromatic hydrocarbons and ketones. These hydrophobic frits can be wetted with organic solvents.
Polyethylene hydrophilic frits are used for general filtration and as clarifications of aqueous solutions and certain other solutions. These hydrophilic frits are specially treated and can consequently be wetted with aqueous solutions. This frit is ideal for gravity flow of an aqueous solution.
Hydrophobic Polyethylene 1/8" Thick for Flash Columns:
PTFE frits can be used to filter almost any organic solvent. They are used for trace analysis and high sensitivity work with solvent detection systems which are not compatible with polyethylene or polypropylene frits. PTFE is a hydrophobic membrane resistant to most organic solvents, acids, and bases.
Polypropylene frits are hydrophobic and are best used for low extractables. Polypropylene frits are similar to PTFE frits in their filtration behavior and serve as an economical alternative to the more expensive PTFE frits.
Note: Most commercial SPE suppliers use hydrophobic polyethylene 20µ frits. Choose another to control flow rate. Larger pore frits are typically used for gravity elution.