VALIDATION STUDIES IN THE REGENERATION OF ION-EXCHANGE CELLULOSES

The effectiveness of a clean-in-place procedure involving treatment with 0.5 M NaOH for 16 h at room temperature has been examined following process-scale chromatography of 1.85 kg hen egg-white proteins on the DEAE-cellulose, Whatman Express-Ion Exchanger D and the QA-cellulose, Whatman Express-Ion Exchanger Q in 251 columns operating at flow-rates of 150 cm/h. Treatment of the media with 0.5 M NaOH did not affect the performance of the media after re-equilibration. The NaOH treatment was effective for sanitization and depyrogenation of columns of Express-Ion D and Express-Ion Q following gross microbial contamination. Furthermore, hydrolysis of the DEAE functional groups from Express-Ion D during treatment with 0.5 M NaOH was beyond the limits of detection, i.e. <0.01% of the total DEAE content of the exchanger.