Formulation of a Concentrated Dispersion as a Carrier for the Delivery of Prostaglandin E2 in the Cervical Canal

Abstract

The use of a concentrated dispersion of swollen polydextrin particles as carrier for the delivery of PGE2 into the cervical canal has been studied. This dispersion should be easily made and expellable from a syringe. However, expelling a concentrated dispersion of swollen polydextrin particles in an 0,9% saline solution through a catheter is problematic since phase separation occurs. Increase of the viscosity of the continuous phase of the dispersion medium on the one hand and interaction of a water soluble polymer with the polydextrin particles on the other hand will prevent phase separation.

Formulation studies on such a dispersion were performed. The studies included the wetting/swelling characteristics, the forces needed to expel the dispersion from a syringe and explanation of these forces by rheological measurements. It was found that the addition of 3% Dextran 70 to 0,9% saline resulted in a viscous dispersion of polydextrin particles that was easy to expel from a syringe through a catheter and which met all the requirements for use as a product for the administration of PGE₂ into the cervical canal.