Acta Pharm. 48 (1998) 93-100

Physico-chemical stability of controlled-release solid dispersion granules containing verapamil^.HCL as active substance

KATERINA GORACINOVA,^1* LJILJANA KLISAROVA,² ANGEL SIMOV,¹ EMILIJA FREDRO-KUMBARADZI,¹ KRISTINA MLADENOVSKA,¹   and   MARIJA GLAVAS¹ 

¹Institute of Pharmaceutical Technology, Faculty of Pharmacy, Vodnjanska 17, Skopje, Macedonia
²Institute of Chemistry, Faculty of Science, P.O.B. 162
University of St. Cyril and Methodius, Skopje, Macedonia  

Physico-chemical stability and drug dissolution profiles of the prepared solid dispersions containing verapamil^.HCL as an active substance were evaluated using different experimental methods. During 60 months of stability testing, no changes were noticed in results of HPTLC, X-ray diffraction, IR and UV spectroscopy studies, pointing to the stability of amorphous drug phase embedded inside the polymer network. Also, no significant changes in the drug-dissolution rate were noticed. The drug release rate dependence upon the Eudragit L content at pH 1.5 was maintained. No changes in the release rate at pH 6.8 occurred, if compared with the products tested immediately after the preparation. Half-change dissolution rate testing showed no significant differences following 60-month stability studies.

Keywords: solid dispersions, stability, controlled release, verapamil^.HCl

back