Preparation and Evaluation in Vitro and in Vivo of Polylactic Acid Microspheres Containing Doxorubicin

Abstract

Polylactic acid microspheres containing doxorubicin were prepared by a solvent evaporation process and release patterns of the drug from the microspheres were examined in vitro. Microspheres with greater drug contents released more drug. The release rate of the drug after the initial burst was found to be small, so that prolonged release was obtainable. It was also found that the wettability of the microspheres might influence the release rate. Venous plasma levels of the drug following intra-arterial administration into dog liver were considerably lower than those following administration of the drug solution. Microangiography revealed embolization due to the microspheres in peripheral arteries in the liver.