STABILITY OF SILICA-BASED TENTACLE-TYPE ION EXCHANGERS AGAINST ALKALI TREATMENT

Treatment of biochromatographic columns with sodium hydroxide is the accepted procedure for CIP-column regeneration and sanitation. But, for silica based materials the well-known sensitivity of the matrix at elevated pH-values restricts the use of this procedure, because life-time of the columns would be reduced drastically. In this investigation it is shown that silica-based tentacle-type ion exchangers have an increased alkali tolerance. Data about the influence of alkali treatment on the chromatographic properties, e.g., protein resolution and protein binding capacities are presented. A possibility of reducing the destructive influence of alkali by additives to the NaOH is shown. Additionally, a new regeneration procedure for column sanitizing based on the use of a weak anionic detergent is introduced.