Gel permeation for the on line removal of proteins from plasma samples prior to HPLC

Gel permeation chromatography (GPC) has been investigated for the on line removal of proteins from plasma samples prior to their analysis by HPLC. The results show that GPC is a mild and effective way to remove proteins from plasma samples. It can very well be coupled on line to HPLC, providing the solutes are suitable for preconcentration on the analytical column itself or on a small pre-column, after the GPC. Under these conditions excellent reproducibility and accuracy can be obtained.