PREPARATION AND EVALUATION OF PHYSICOCHEMICAL PROPERTIES OF MUCOADHESIVE, FREEZE-DRIED BUCCAL SYSTEMS WITH SELEGILINE
|Marcin Płaczek , Małgorzata Sznitowska|
Medical University of Gdańsk, Department of Pharmaceutical Technology, Hallera 107, Gdańsk 80-416, Poland
Selegiline, a selective, irreversible inhibitor of monoamine oxidase type B, is widely used in the treatment of Parkinson's disease. This drug, after oral administration, undergoes extensive metabolism (mainly in the liver) and therefore the absolute bioavailability is only about 10% . This problem can be solved by special drug formulations that are not designed for swallowing but release selegiline in the mouth and buccal absorption prevents first - pass effect . Until now neither of these formulations provides an extended release of selegiline.
The aim of the study was to develop and evaluate a new mucoadhesive, buccal dosage form for selegiline, prepared by lyophilization, which enables the release of the drug during a few hours (optimally for 4 - 6 h) by means of the multiparticulate structure.
The study comprised of: selection of a mucoadhesive polymer for preparation of the drug carrying matrix of the lyophilized system, preparation of prolonged-release particles with selegiline (microspheres or coated pellets) and incorporation of these forms in the matrix. The microspheres of selegiline were prepared by emulsification method, using ethylcellulose as the polymer forming microspheres and the mixture of acetone and ethanol as solvent. The microspheres were formed by emulsifying the solution of drug and polymer in liquid paraffin and evaporation of the volatile solvents. Pellets were made by extrusion - spheronisation method and coated in a fluid - bed coater. Aqueous dispersion of ethylcellulose was chosen as a coating material. The obtained extended release forms of selegiline were incorporated into the carbomer viscous solution, which was dosed into blisters.
Experimental methods comprised of: visual and microscopic inspection, drug loading and release profiles both from the microspheres or pellets and from the freeze - dried system as well as organoleptic and bioadhesion analysis of the placebo systems. In vitro studies of mucoadhesion, using texture analyzer are also planed.
The obtained results show, that it is possible to prepare freeze - dried systems with prolonged release of the drug. Incorporation into the mucoadhesive matrix small polymeric reservoirs: microspheres and pellets containing the selegiline hydrochloride enables to obtain system, which will release the drug for a period of 5 - 6 hours. Carbomer can be used as the adhesive component although time of its mucoadhesion in vivo was only about 2 hours and the composition requires modification. The mucoadhesive properties of the system can be also explained by the texture analysis.
Presentation: Poster at V Multidyscyplinarna Konferencja Nauki o Leku, by Marcin Płaczek
See On-line Journal of V Multidyscyplinarna Konferencja Nauki o Leku
Submitted: 2006-01-30 12:51 Revised: 2009-06-07 00:44