Preparation of sustained release microspheres containing extracts from Caulis sinomenii with polylactic acid and their release property in vitro / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>To prepare polylactic acid microspheres containing total alkaloid extracts of Caulis sinomenii and study their release characteristics in vitro.</p><p><b>METHOD</b>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.</p><p><b>RESULT</b>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%.</p><p><b>CONCLUSION</b>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.</p>