How specific is Phree for removing only phospholipids?

Phree is very specific to phospholipids.  Analogs of phospholipids, such as long chain fatty acids may also be removed.  This is an added benefit for analyses from biological samples.  Very few analytes are as hydrophobic as phospholipids so analyte retention on Phree is not a concern.  Although there is no method development required to use Phree, it is still important to know what the analytes of interest are to make sure Phree is appropriate for the application.