Abstract
Methoxy polyethylene glycol and poly(D, L-lactide) (mPEG/PLA) copolymers with various composition were synthesized by using ring-opening polymerization method and characterized by Fourier transform infrared spectroscopy (FT-IR). mPEG/PLA microspheres were prepared by double emulsion method. 5-fluorouracil (5-FU), as an anticancer drug, was successfully loaded in these microspheres. The obtained microspheres were characterized for entrapment efficiency, drug loading, and in-vitro release studies and subjected to optical microscopy and scanning electron microscopy (SEM). The results indicated that the microspheres showed spherical shape, homogeneous particle size distribution and smooth surfaces. The percentage of loading and encapsulation efficiency of 5-FU decreased with increasing amount of mPEG in the microspheres and decreasing concentration of mPEG/PLA. 5-FU showed a typical bimodal in-vitro release behavior from mPEG/PLA microspheres and the release kinetics indicated Fickian diffusion. In-vitro cytotoxicity analysis on HT-29 cell lines demonstrated that 5-FU loaded mPEG/PLA microspheres possess the potential to delay the apoptosis for a long time.
ACKNOWLEDGMENTS
This project was financially supported by the National Natural Science Foundation of China (Nos. 51202087 and 51262008) and the Research Foundation of Education Bureau of Human Province, China (Nos. 12A109 and 11B099).