Injectable implant would be a potential way for
2-methoxyestradiol (2-ME) for the
therapy of
breast cancer because of its water-insolubility, short half-life, and low oral bioavailability. So
2-ME microspheres based on
poly (DL-lactide-co-glycolide) were prepared by
emulsion solvent extraction method and characterized for morphology, particle size,
drug physical state, entrapment efficiency and drug release in vitro and in vivo. Their cytotoxicity on MCF-7 cells was evaluated by
sulforhodamine B (SRB) method. The
2-ME was successfully entrapped in the interior of
microspheres with particle size of 55.44 ± 12.21 μm and could exist in an amorphism. In vitro and in vivo release of
2-ME from the
microspheres occurred in a Ritger-Peppas and zero-order manner with a slow release over 46 days, respectively, and their better correlation was found. The
2-ME even with very low concentration in the
microspheres could efficiently inhibit the growth of MCF-7 cells compared to the equivalent amount of
drug in free
solution, which indicated that the release rate from the
microspheres and local water-solubility of
2-ME could maintain effective
drug concentration in target site. The above results indicated that the
microspheres prepared could not only control prolonged release of
2-ME in vitro and in vivo but also maintain effective
drug concentration in target site. So
2-ME microspheres are acceptable for controlled release devices for effective treatment of
breast cancer.