[Preparation of sustained release microspheres containing extracts from Caulis sinomenii with polylactic acid and their release property in vitro].

OBJECTIVE

To prepare polylactic acid microspheres containing total alkaloid extracts of Caulis sinomenii and study their release characteristics in vitro.

METHOD

Polylactic acid microspheres containing total alkaloid extracts of C. sinomenii were prepared by O/W emulsification solvent-evaporation process. The microspheres were characterized in terms of morphology, encapsulation efficiency, and particle size distribution. The effect of different conditions on release property of microspheres was studied.

RESULT

The formed microspheres were spherical with smooth surfaces. The encapsulation efficiency and rate of drug loading were (83.4 +/- 5.63)% and (8.7-0.35)%, respectively. The distribution of particle size was uniform and the average size was (21.5 +/- 1.22) microm. In vitro release study revealed that the 32-hour accumulative release percentage reached 80%.

CONCLUSION

Polylactic acid microspheres containing total alkaloid extracts of C. sinomenii were prepared successfully. Microspheres with good sustained-release characteristics can be produced by controlling different process parameters.