Thymopentin loaded Microsphere Preparation by w/o/w Emulsion Technique: In Vitro/ex Vivo Evaluation

Abstract

Poly-D, L-lactide (PDLLA) and polylactide-co-glycolide (PLGA) microspheres containing thymopentin have been prepared by a water-in-oil-in-water-emulsion/solvent evaporation technique. The goal is to stabilize the active compound thymopentin, and to prolong its therapeutic activity, by embedding the drug in a polymeric matrix. The microspheres obtained have been characterized for their morphology and drug content. In-vitro dissolution tests have been performed on the microspheres. Results show that the type of polymer employed (PDLLA or PLGA) does not seem to affect microsphere morphology, while in-vitro dissolution profiles are greatly influenced by the composition of polymer matrix. Ex-vivo evaluation of PLGA microspheres performed on mouse thymocites shows that biological activity of Thymopentin is maintained after loading into PLGA microspheres.

Key Words:

• Microspheres
• poly(lactide)
• w/o/w emulsion
• poly(lactide-co-glyco-lide)
• thymopentin