Study on the in vitro release of tetanus toxo id from polylactide microspheres and the influence of additives on the drug release / 北京大学学报(医学版)

ABSTRACT

Objective: To study on in vitro release of tetanus toxoid contained in polylactide microsp heres and the influence of additives on the drug release. Methods: Some parameters affecting the rate of release were asse ssed during the in vitro experiments lasted 84 days (1)the molecular mass of the poly mers , (2)the protein loading of the microspheres, (3)the particle sizes, (4)co-enca p sulation of additives. Results: The polylactide microspheres con taining tetanus toxoid presented considerable sustained release effect. Release kinetics of the microspheres fitted in with zero order equations. The rate of release was shown to dep end on the four parameters mentioned above. Conclusion: The poly lactide microsph eres investigated may be prospective for the development of controlled release v accines.