Abstract: A method is provided for purifying physiologically active proteins, especially antibodies, in order to remove impurities such as DNA contaminants and viruses with minimal loss of physiologically active proteins. The physiologically active protein is introduced into an aqueous solution of low conductivity at a pH of below the isoelectric point of the physiologically active protein to precipitate impurities as particles. The particles are removed, leaving a purified physiologically active protein.

Abstract: A method is provided for purifying physiologically active proteins, especially antibodies, in order to remove impurities such as DNA contaminants and viruses with minimal loss of physiologically active proteins. The physiologically active protein is introduced into an aqueous solution of low conductivity at a pH of below the isoelectric point of the physiologically active protein to precipitate impurities as particles. The particles are removed, leaving a purified physiologically active protein.

Abstract: A method for manufacturing an antibody formulation in which DNA contaminants are removed by binding the antibody to a protein-A or probtin-G affinity column and eluting the antibody with an acidic eluting solution, preferably of low conductivity.

Abstract: A method for manufacturing an antibody formulation in which DNA contaminants are removed by binding the antibody to a protein-A or probtin-G affinity column and eluting the antibody with an acidic eluting solution, preferably of low conductivity.

Abstract: A method for manufacturing an antibody formulation in which DNA contaminants are removed by binding the antibody to a protein-A or probtin-G affinity column and eluting the antibody with an acidic eluting solution, preferably of low conductivity.

Abstract: A method is provided for purifying physiologically active proteins, especially antibodies, in order to remove impurities such as DNA contaminants and viruses with minimal loss of physiologically active proteins. The physiologically active protein is introduced into an aqueous solution of low conductivity at a pH of below the isoelectric point of the physiologically active protein to precipitate impurities as particles. The particles are removed, leaving a purified physiologically active protein.

Abstract: Problems to be Solved: The present invention provides a simpler and less expensive method for purifying physiologically active proteins, especially antibodies, which can ensure removal of impurities such as DNA contaminants and viruses, and which can minimize a loss of physiologically active proteins. Means for Solving the Problems: A method for removing impurities in a physiologically active protein-containing sample, which comprises the following steps: 1) allowing the physiologically active protein-containing sample to be converted into an aqueous solution of low conductivity at a pH below the isoelectric point of the physiologically active protein; and 2) removing the resulting particles.