Polylactic Acid Microspheres as A Potential Vaccine Delivery System for the Tetanus Toxoid: Preparation and In Vitro Dissolution Study

The objective of the present work is to develop Tetanus Toxoid (TT) loaded Polylactic Acid microspheres for controlled delivery. The microsphere was prepared by emulsion cross-linking technique using polymer Polylactic Acid. Dichloromethane and Gluteraldehyde saturated Toluene were used as solvent and cross-linking agent respectively. Tetanus Toxoid was loaded into the microspheres by the two methods i.e. adsorption and encapsulation. The prepared microspheres were accessed for size, uniformity, shape, surface charateristics and percentage yield. The estimation of TT incorporated into PLA microspheres is done by the Lime Flocculation test procedure. In vitro dissolution studies were done with both TT adsorption and encapsulated microspheres for 96 hours and 60 days respectively. The resulting microspheres having smooth surface, spherical and free flowing. On the basis of above studies, it can be concluded that the TT encapsulated PLA microspheres showed higher encapsulation efficiencies and maximum prolongation of TT release.