Answer
To protect the column against foreign particles which could have an adverse influence on the separation efficiency, we advise you to subject the eluent to microfiltration (0.45 µm filter) and to siphon the eluent through the 6.2821.090 Aspirating filter.
To avoid contamination by abrasive particles arising from piston seals of the high-pressure pump, it is advantageous to install an inline filter between the pump and the injection valve.
The use of readily interchangeable precolumns serves to protect the actual separating columns and increase their lifetime appreciably. Further the Metrohm Inline Ultrafiltration respectively Dialysis can protect the column from unwanted components of the sample.