Polymer micelles containing anthracylines for the treatment of cancer

An anthracycline loaded micelle comprising a multiblock copolymer, wherein said micelle has a drug-loaded inner core, a crosslinked outer core, and a hydrophilic shell, wherein the multiblock copolymer is of formula IX:

• wherein:
• each n is independently 10-2500;
• each s is independently 1 or 2
• each w is independently 0-30;
• each x is independently 1-30;
• each y is independently 5-50;
• each z is independently 5-50;
• M is Fe;
• and
• each R1 is independently —N3—OCH3 or
• wherein T is a targeting group moiety.