Analysis and evaluation of filter cartridge extractables for validation in pharmaceutical downstream processing

This paper describes a comprehensive approach for the extractables analysis of filter cartridges used in pharmaceutical production processes. For the extraction of the cartridges, two model solvents (water and ethanol) and worst case conditions are used. The extracts of 8 cartridges from various filter manufacturers are analysed both in the original and the concentrated form to gain data about the high and low concentrated contaminants, implementing standard analytical techniques such as GC-MS, RP-HPLC, GPC and FT-IR. Degradation products and additives of the filter cartridge polymers are found to be the source of most of the extracted compounds. The concentrations of extractables are determined in the range of ppm to ppb per cartridge under the applied extraction conditions. The effect of rinsing the cartridges prior to use was studied, showing a reduction of the extractables even after small flush volumes.