Small scale hydraulic membrane resistance measurement by analytical multi-sample photo-centrifugal filtration (ACF)

The continuous development of new products in pharmaceutical and biotechnology industries requires efficient and scalable separation processes. Standardized laboratory tests for hydraulic resistance of filtration membrane typically demand large membrane areas and substantial suspension volumes. Analytical photo-centrifugal filtration (ACF) offers a novel approach for high-throughput membrane characterization using minimal sample volumes. Based on continuous in-situ measurement of space- and time-resolved light transmission, ACF determines filtrate volume via STEP-Technology®. Unlike conventional pressure-driven methods, ACF operates without external pressure and requires minimal cleaning. Its flexible design allows parameter adjustments by varying rotor speeds or temperature profiles within a single experiment. In contrast to the conventional method (VDI 2762), several samples can be measured at once. This study presents an improved filtration cell for ACF and demonstrates the comparability of membrane resistances measured by ACF and VDI 2762. A polypropylene membrane with a nominal pore size of approximately 0.1 μm was used. Challenges and future opportunities are also discussed. • Novel method for characterizing filter medium resistance using minimal sample volume, benchmarked against VDI 2762. • Implementation of constant-pressure conditions for filtration under centrifugal force. • Experiments with ACF demonstrate strong agreement with VDI 2762 reference measurements.