Amphiphilic block copolymer, method for preparing the same, and micellar drug encapsulation system formed of the copolymer and an antitumor agent

摘要

The present invention relates to a novel amphiphilic block copolymer and the preparation method thereof, as well as a micellar drug-loaded system formed by said copolymer and an anti-tumor drug. Said amphiphilic block copolymer comprises a hydrophilic segment and a hydrophobic segment, and the end group of said hydrophobic segment is end-capped with a hydrophobic group. Methoxypolyethylene glycol (or polyethylene glycol)-polyester block copolymer which has recognized safety is used as a fundamental material of the amphiphilic block copolymer of the present invention, and the terminal hydroxyl group of the polyester segment is modified with a hydrophobic group, whereby the compatibility between the drug molecule and the hydrophobic segments of the block copolymer is improved, and the interaction therebetween is enhanced. Moreover, a larger space for accommodating the drug molecules is provided. Said micelles are more effective in restricting the drug molecules inside the micellar core and preventing the drug from dissolved out of the micelles. Therefore, a drug-loaded micelle with high stability is obtained.