Modification of the dissolution rate and, thus, the enhancement of the bioavailability of a dopaminergic
drug,
piribedil, which has a low aqueous solubility and short elimination half-life have been the aim in this study. Preparations of micron and submicron particles using solid
lipid carriers have been performed for this purpose. For the avoidance of
solvent residues resulting from the preparation technique, cold and hot homogenization methods have been used to prepare solid
lipid particles. After obtaining an appropriate particle size,
piribedil loading and preparation yield by the use of those two methods, various formulations have been prepared with different
lipid,
drug and
surfactant materials. The factors mentioned were found to affect properties of the particles, and the release rate was found to be the fastest in acidic medium.
Suspensions of pure
piribedil and a formulation, selected according to the results obtained from in vitro dissolution and particle size experiments, were compared using
tremor tests in mice. The same
suspensions were applied perorally to rabbits and bioavailability of the solid
lipid particle was found to be higher than the pure
piribedil. After an in vitro-in vivo evaluation of
piribedil solid
lipid particles developed for
Parkinson's disease therapy, it has been determined that release rate could be controlled and
piribedil bioavailability could be improved.