Abstract: A method, a system and a use of a single use mixing bag for performing alkaline lysis, neutralisation and clarification of bacterial cells for extraction of plasmid DNA. The method comprises providing a suspension of bacterial cells and providing alkaline lysis solution into a single use mixing bag for performing an alkaline lysis of said bacterial cells, wherein said single use mixing bag comprises an integrated mixer. The method comprises furthermore mixing of the content in the single use mixing bag by the integrated mixer during the alkaline lysis and stopping the alkaline lysis by the addition of a neutralisation solution into the single use mixing bag and clarifying the content in the single use mixing bag after the alkaline lysis has been performed by the addition of a flocculate lifting agent into the single use mixing bag, whereby at least two phases are separated inside the single use mixing bag, whereby one of said phases is a neutralised and clarified alkaline solution comprising plasmid DNA.

Abstract: The invention relates to a device for separating unwanted compounds from an antibody containing biological sample. The device comprises a porous support and a polymeric resin disposed within the pores of the porous support. The device may further comprise a viral clearance membrane upstream or downstream from the polymeric resin. Methods of use are also provided.