The Metrosep I Trap 1 - 100/4.0 column is used to eliminate ionic, i.e. cationic and anionic, contaminants from aqueous solutions. Its use is especially recommended for the purification of the transfer water in combination with "MISP" or "Metrohm Inline Sample Preparation". Using the Metrosep I Trap 1 - 100/4.0 column can significantly reduce the influence of the transfer water on the system blank.