Protein purification device

A method for purifying protein from a protein-containing fluid comprising the steps of:

• providing a device comprising a prefilter unit containing at least one size exclusion filter, a membrane adsorber unit containing a porous membrane, and a collecting container, wherein the prefilter unit is located inside or partially inside the membrane adsorber unit, and the membrane adsorber unit is located inside or partially inside the collecting container;
• filling the prefilter unit with the protein-containing fluid;
• centrifuging the device, wherein constituents of the protein-containing fluid that cake the porous membrane of the membrane adsorber unit are retained by the at least one size exclusion filter, and the protein is adsorbed on the porous membrane of the membrane adsorber unit and a filtrate collects in the collecting container;
• removing the prefilter unit and the filtrate located in the collecting container;
• filling the membrane adsorber unit with elution buffer solution;
• eluting the protein adsorbed on the porous membrane with the elution buffer solution in the collecting container, to obtain purified protein.