High entrapment efficiency of chitosan/polylactic acid/tripolyphotspate nanosized microcapsules for rapamycin by an emulsion-evaporation approach.

Chitosan (CS)/polylactic acid (PLA)/tripolyphotspate (TPP) nanosized microcapsules were prepared by emulsion-evaporation. The average diameter of the obtained nanosized microcapsules was around 100-300 nm, and a homogeneous size distribution and good dispersion were observed. The entrapment efficiency of the nanosized CS/PLA/TPP microcapsules for rapamycin was increased with the increase in amount of PLA. When the ratio of CS to PLA was 80 to 20, the entrapment efficiency of CS/PLA/TPP nanosized microcapsules for rapamycin reached the highest (89.8 +/- 1.72%). It was also observed that The RAPA entrapment efficiency reached its highest at 20% of addition dosage of RAPA.