Preparation and evaluation of sustained-release polylactic acid microspheres of bupivacaine in vitro / 第二军医大学学报

ABSTRACT

Objective: To prepare sustained-release polylactic acid microspheres containing bupivacaine (BUP-PLA-MS) and to measure its dissolution in vitro. Methods: BUP-PLA-MS was prepared with polylactic acid (PLA) as carriers using the water-in-oil-in-water (W/O/W) emulsion solvent evaporation method. The powder particle characteristics of BUP-PLA-MS were evaluated comprehensively, and its dissolution characteristics in vitro were studied. Results: It was indicated that bupivacaine formed molecular dispersion within PLA matrix by differential thermal analysis(DTA). The in vitro release behavior of bupivacaine could be best described by Higuchi equation, with t 1/2 =22.76 h. Conclusion: Release of bupivacaine from microspheres is sustained in vitro.