Abstract: Disclosed is a composition comprising a silicon-containing compound represented by the general formula (1) mentioned in the description of the present application, at least one compound of the general formula (2-1) or (2-2) in which m is an integer of 3 or greater mentioned in the description of the present application, and optionally a compound represented by the general formula (3). The total amount of the silicon-containing compound of the general formula (2-1) or (2-2) in which m is an integer of 3 or greater is more than 0 ppm and 46,000 ppm or less based on the total weight of the silicon-containing compounds of the general formulas (1), (2-1), (2-2), and (3). The composition is used for producing a polyimide precursor obtained by copolymerizing a silicon-containing compound, tetracarboxylic dianhydride, and diamine.

Abstract: A module includes a bonded portion in which the hollow-fiber-membranes are bonded and fixed together by potting material at least in an end portion of each of the hollow-fiber-membranes. Each of the hollow-fiber-membranes has a resin impregnation portion in which resin is impregnated into an outer surface side of each of the hollow-fiber-membranes at least in the end portion where each of the hollow-fiber-membranes is bonded and fixed together. In the end portion of the hollow-fiber-membranes, a leading edge of the resin impregnation portion toward the other end of each of the hollow-fiber-membranes is located closer to the other end than a leading edge of the bonded portion toward the other end. The thickness of the resin impregnation portion in the direction of the wall thickness of the hollow-fiber-membranes is 10 to 70% with respect to the thickness of the hollow-fiber-membranes.

Abstract: A module includes a bonded portion in which the hollow-fiber-membranes are bonded and fixed together by potting material at least in an end portion of each of the hollow-fiber-membranes. Each of the hollow-fiber-membranes has a resin impregnation portion in which resin is impregnated into an outer surface side of each of the hollow-fiber-membranes at least in the end portion where each of the hollow-fiber-membranes is bonded and fixed together. In the end portion of the hollow-fiber-membranes, a leading edge of the resin impregnation portion toward the other end of each of the hollow-fiber-membranes is located closer to the other end than a leading edge of the bonded portion toward the other end. The thickness of the resin impregnation portion in the direction of the wall thickness of the hollow-fiber-membranes is 10 to 70% with respect to the thickness of the hollow-fiber-membranes.

Abstract: A method for producing a protein adsorbent comprising a substrate and a molecular chain fixed on the surface of the substrate is disclosed. The method comprises, in this order: a dry-heat treatment step of heating a pretreatment adsorbent comprising the substrate and the molecular chain fixed on the surface of the substrate, in which the molecular chain contains a weak electrolytic ion-exchange group; and a wet-heat treatment step of heating the pretreatment adsorbent in a moistened state with a liquid or steam to obtain the protein adsorbent.

Abstract: A method for producing a protein adsorbent comprising a substrate and a molecular chain fixed on the surface of the substrate is disclosed. The method comprises, in this order: a dry-heat treatment step of heating a pretreatment adsorbent comprising the substrate and the molecular chain fixed on the surface of the substrate, in which the molecular chain contains a weak electrolytic ion-exchange group; and a wet-heat treatment step of heating the pretreatment adsorbent in a moistened state with a liquid or steam to obtain the protein adsorbent.

Abstract: A method is disclosed for purifying an antibody monomer, comprising providing a porous membrane comprising a hydrophobic porous substrate, a hydrophilic molecular chain of a different material from that of the porous substrate, immobilized on the surface of pores of the porous substrate, and a side chain of the molecular chain, containing a nitrogen atom to which one to three alkyl groups each having two or three carbon atoms are bonded; passing an antibody solution containing antibody aggregates of dimers or higher-order multimers through the porous membrane to adsorb the antibody aggregates to the porous membrane; and recovering the purified antibody monomer in the passed solution.

Abstract: It is an object of the present invention to provide a method for eluting an adsorbed protein that suppresses a decrease in protein adsorption ability, in a method for purifying a protein using a protein-adsorbing porous membrane. The present invention provides a method for purifying a protein, comprising an adsorption step and an elution step, wherein in the elution step, at least one eluent is passed in the opposite direction with respect to the direction of the passage of a stock solution containing an adsorption target protein, in the adsorption step.

Abstract: A method for producing a protein adsorbent comprising a substrate and a molecular chain fixed on the surface of the substrate is disclosed. The method comprises, in this order: a dry-heat treatment step of heating a pretreatment adsorbent comprising the substrate and the molecular chain fixed on the surface of the substrate, in which the molecular chain contains a weak electrolytic ion-exchange group; and a wet-heat treatment step of heating the pretreatment adsorbent in a moistened state with a liquid or steam to obtain the protein adsorbent.

Abstract: It is an object of the present invention to provide a method for eluting an adsorbed protein that suppresses a decrease in protein adsorption ability, in a method for purifying a protein using a protein-adsorbing porous membrane. The present invention provides a method for purifying a protein, comprising an adsorption step and an elution step, wherein in the elution step, at least one eluent is passed in the opposite direction with respect to the direction of the passage of a stock solution containing an adsorption target protein, in the adsorption step.

Abstract: The present invention provides a method for purifying a protein to remove impurities from a mixture liquid containing a desired protein and the impurities, comprising the step of performing filtration using a porous membrane having a graft chain on a pore surface and an anion-exchange group fixed to the graft chain.

Abstract: The hollow fiber membrane module has a hollow fiber membrane bundle composed of a plurality of hollow fiber membranes with an adsorption function, a housing that houses the hollow fiber membrane bundle, and partition members that partition the hollow fiber membrane bundle into a plurality of small bundles at an end of the hollow fiber membrane bundle, the partition members having penetrating sections that penetrate in the lengthwise direction of the hollow fiber membranes. The volume fill factor of the hollow fiber membranes is at least 30% and less than 70%. This can secure throughput capacity for the hollow fiber membrane module, while maintaining consistent adsorption capacity per unit membrane volume, thus ensuring high scalability.

Abstract: The present invention provides a method for purifying a protein to remove impurities from a mixture liquid containing a desired protein and the impurities, comprising performing filtration using a porous membrane having a graft chain on a pore surface and an anion-exchange group fixed to the graft chain.

Abstract: A method is disclosed for purifying an antibody monomer, comprising providing a porous membrane comprising a hydrophobic porous substrate, a hydrophilic molecular chain of a different material from that of the porous substrate, immobilized on the surface of pores of the porous substrate, and a side chain of the molecular chain, containing a nitrogen atom to which one to three alkyl groups each having two or three carbon atoms are bonded; passing an antibody solution containing antibody aggregates of dimers or higher-order multimers through the porous membrane to adsorb the antibody aggregates to the porous membrane; and recovering the purified antibody monomer in the passed solution.

Abstract: The present invention provides a method for purifying a protein to remove impurities from a mixture liquid containing a desired protein and the impurities, comprising the step of performing filtration using a porous membrane having a graft chain on a pore surface and an anion-exchange group fixed to the graft chain.