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: An object of the present invention is to provide a method for purifying a protein capable of significantly reducing amount of impurities and achieving a high recovery rate, compared to a method for purifying a protein using an activated carbon of the related art. The present invention relates to a method for purifying a protein using an activated carbon, including: bringing an activated carbon pretreatment solution obtained by adjusting conductivity of a protein-containing aqueous solution into contact with an activated carbon; separating the protein and impurities in a non-adsorption mode to obtain the protein of interest with a low content of impurities.