Membrane filtration

A method in which a liquid is filtered through a membrane, typically 0.45 µm, that retains micro-organisms, which are then incubated on agar or in liquid media. It is used for sterility testing, water testing, bioburden and MLT of antimicrobial products. Rinsing the membrane removes inhibitory substances, and large volumes can be tested to improve sensitivity. The membrane type and rinse procedure are confirmed in method suitability.