Scale-up of Sterilizing-grade Membrane Filters from Discs to Pleated Cartridges: Effects of Operating Parameters and Solution Properties

Abstract

Scale-up remains at the core of a process development. For direct flow sterilizing-grade filtration, a linear scale-up between the performance of discs and pleated filter cartridges has traditionally been assumed. Linear scale-up assumes that the filtration performances, defined here as filter flux and capacity, scale linearly with the membrane area and remains independent of the selected device formats. However, experimental results show that the later assumption does not hold in all cases. We investigated the effect of solution properties and operating parameters on scale-up from membrane disc to pleated filter cartridges. Typical values of flux and capacity ratios and the guidelines on scale-up of direct flow filters from bench-scale to manufacturing-scale are presented. Specifically, we found that the flux ratio for pleated filter and small-scale disc range from 0.5 to 0.85, and capacity ratio for most cases is within ±20% variation of unity, with some exceptions.