Block copolymer reduced in impurity content, polymeric carrier, pharmaceutical preparations in polymeric form and process for the preparation of the same

摘要

A process for purification which permits satisfactory removal of impurities from a block copolymer consisting essentially of polyethylene glycols and poly(acidic amino acid) and is suitable for the production of a polymeric carrier having a pharmaceutically acceptable purity; a process for producing such a polymeric carrier; a block copolymer reduced in impurity content; a polymeric carrier as described above; pharmaceutical preparations in polymeric form, produced by the use of the carrier; and a method of subjecting polyethylene glycols and poly(acidic amino acids)-which are impurities contained in the block copolymer-to treatment with either an ion-exchange resin or a partition/absorption resin and then determining the quantities of them with a gel filtration column.