The invention relates to a process for the selective concentration of immunoglobulins or other proteins that contain an Fc domain (target protein), comprising the following steps: a. preparing a solution that contains the target protein; b. incorporating an Fc-binding protein with precisely two binding sites under conditions that allow binding to occur; c. separating the precipitate from the liquid phase; d. undoing the binding of the target protein from the Fc-binding protein.

The invention relates to a process for the selective concentration of immunoglobulins or other proteins that contain an Fc domain (target protein), comprising the following steps: a. preparing a solution that contains the target protein; b. incorporating an Fc-binding protein with precisely two binding sites under conditions that allow binding to occur; c. separating the precipitate from the liquid phase; d. undoing the binding of the target protein from the Fc-binding protein.

The present invention relates to method for purifying proteins naturally occurring in mammalian milk from aqueous protein solution using water-soluble silicate. The silicates form an insoluble precipitate of a silicate-protein complex from which the proteins can be isolated.

The present invention relates to method for purifying proteins naturally occurring in mammalian milk from aqueous protein solution using water-soluble silicate. The silicates form an insoluble precipitate of a silicate-protein complex from which the proteins can be isolated.

The present invention relates to a polypeptide separation method including a step (step A) of mixing the polypeptide, which is a monoclonal antibody, and a ligand in a liquid to form a complex of the polypeptide and the ligand and to obtain a liquid containing the complex, and a step (step B) of filtering the liquid containing the complex obtained in the step A.

The present invention relates to a polypeptide separation method including a step (step A) of mixing the polypeptide, which is a monoclonal antibody, and a ligand in a liquid to form a complex of the polypeptide and the ligand and to obtain a liquid containing the complex, and a step (step B) of filtering the liquid containing the complex obtained in the step A.

In certain embodiments, the invention provides a method of purifying a protein of interest from a mixture which comprises the protein of interest and one or more contaminants, comprising: a) subjecting the mixture to a first chromatography step; b) recovering the protein of interest in an elution solution; c) adding caprylic acid to the elution solution to form a contaminant precipitate; d) removing the contaminant precipitate from the elution solution; and e) subjecting the post-precipitated elution solution to a second chromatography column, thereby purifying the protein of interest.

In certain embodiments, the invention provides a method of purifying a protein of interest from a mixture which comprises the protein of interest and one or more contaminants, comprising: a) subjecting the mixture to a first chromatography step; b) recovering the protein of interest in an elution solution; c) adding caprylic acid to the elution solution to form a contaminant precipitate; d) removing the contaminant precipitate from the elution solution; and e) subjecting the post-precipitated elution solution to a second chromatography column, thereby purifying the protein of interest.

The present invention relates to a method for suppressing aggregation of polypeptide. Specifically, the present invention relates to a method for suppressing, in a solution comprising an antibody or an Fc region-containing protein, formation of an aggregate derived from an antibody or an Fc region-containing protein having a non-native conformation, the method comprising: the steps of (i) binding an AF.2A1 polypeptide or an analog thereof with an aggregate derived from the antibody or Fc region-containing protein having a non-native conformation in the solution; and (ii) collecting the aggregate bound to the polypeptide or analog thereof from the solution.

The present invention relates to a method for suppressing aggregation of polypeptide. Specifically, the present invention relates to a method for suppressing, in a solution comprising an antibody or an Fc region-containing protein, formation of an aggregate derived from an antibody or an Fc region-containing protein having a non-native conformation, the method comprising: the steps of (i) binding an AF.2A1 polypeptide or an analog thereof with an aggregate derived from the antibody or Fc region-containing protein having a non-native conformation in the solution; and (ii) collecting the aggregate bound to the polypeptide or analog thereof from the solution.