In Vitro Characterization of Methotrexate-Loaded Poly(Lactic Acid) Microspheres of Different Molecular Weights

AbstractMethotrexate-loaded poly (lactic acid) (PLA) microspheres were prepared from three different molecular weight PLAs using the emulsiflcation-solvent evaporation method. The in vitro drug release could be controlled for up to 2 to 3 weeks. The release of the drug was dependent on the molecular weight of the polymer, the fastest release being from microspheres prepared with the lowest molecular weight PLA. This technique allows control of drug release with a single biodegradable homopolymer.