V. Ratsimbazafy et al., INFLUENCE OF THE MANUFACTURING PROCESS ON THE RELEASE OF PROXYPHYLLINE FROM LIPID MATRICES, Die Pharmazie, 52(11), 1997, pp. 863-866
Four manufacturing processes were used to prepare lipid matrices conta
ining glyceryl tristearate (70%) and tribehenate (30%). Solid dosage f
orms were direct compression tablets and three others obtained by melt
ing-congealing: monolithic capsules, granulate capsules and granulate
tablets of four different diameters (5, 6, 7 and 12 mm). Huge differen
ces in proxyphylline release rates were noticed, essentially owing to
the clearly distinct dissolution surfaces of the various dosage forms.
Drug release increased from monolithic capsule successively to granul
ate tablets, direct compression tablet and granulate capsule. Concerni
ng the granulate tablets of four different diameters, the release incr
eased linearly with the dissolution surface. Except for the granulate
capsule that did not give an actual matrix, the release mechanism was
Fickian diffusion and did not change with either the manufacturing pro
cess or with the dissolution surface.