Abstract: A synthetic adsorbent, where a maximum value of a differential pore volume under a pressure condition of 0.5 to 30.0 psia is greater than 0.05 mL/g. A method of measuring the differential pore volume includes reducing a pressure in a sample container where the synthetic adsorbent that has been dried is placed to 10 Pa or less, mercury is degassed by reducing the pressure to 10 Pa or less, and the sample container is filled with the mercury at a pressure of 0.5 psia, measuring a mercury intrusion amount when the pressure in the sample container filled with the mercury is increased from 0.5 to 30.0 psia, and calculating the differential pore volume by dividing an amount of an increase in the mercury intrusion amount when a first-stage pressure calculated based on the mercury intrusion amount measured in the measuring is increased, by a measured amount of the synthetic adsorbent.

Abstract: 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.