Characterization of water‐soluble polymers and aqueous colloids with asymmetrical flow field‐flow fractionation

A study on the retention and separation of water‐soluble polymers and globular proteins by asymmetrical flow field‐flow fractionation (Asym. flow FFF) is presented. The applicability of only one carrier liquid to a great variety of samples with different charge stabilization and morphology (in order to simplify the handling and the data evaluation) is demonstrated. With this carrier liquid, the investigation of polystyrene latex beads with anionic as well as cationic surfactants, anionic polystyrene sulfonates and globular proteins in the hydrodynamic radius range 10–400 nm is presented, thus resulting in linear calibration curves as well as in the ability for the absolute determination of the diffusion coefficient as well as its distribution. The averaged plate number of the presented flow channel under the applied standard conditions is determined to be in the order of 1 500 which demonstrates the potential of this technique. Preliminary experiments with commerical, broadly distributed poly(1‐vinyl‐2‐pyrrolidone) samples show that the experiment performed at model systems can easily be extended to technical polymers of commercial interest.