RESUMO
Felodipine is a second generation calcium channel blocker widely used as antihypertensive and antianginal drug which belongs to BCS class II category. Hence, its low water solubility limits the pharmacological effect. The aim of this study was to improve the dissolution rate of felodipine using spherical agglomeration technique with acetone, water and dichloromethane as good solvent, poor solvent and bridging liquid, respectively. The quasi emulsion solvent diffusion technique was used as a method for spherical agglomeration. Inutec SP1 was used as an emulsion stabilizer and as hydrophilic polymer in agglomeration process. The FTIR and DSC results showed no change in the drug after crystallization process. PXRD studies showed sharp peaks in the diffractograms of spherical agglomerates with minor reduction in height of the peaks. The particle size of spherical agglomerates (FI-2) was about 134.33 ± 13.57 µm, n=3 and the dissolution efficiency of felodipine up to 120 min increased to about 4-fold in phosphate buffer containing 1.8% Tween 80 (pH 6.8). Spherical agglomerates showed enhanced solubility compared to untreated powder possibly due to the partial conversion to amorphous form.
RESUMO
An oral controlled release suspension of chlorpheniramine maleate was prepared using ion-exchange resin technology. A strong cation exchange resin Indion 244 was utilized for the sorption of the drug and the drug resinates was evaluated for various physical and chemical parameters. The drug-resinate complex was microencapsulated with a polymer Eudragit RS 100 to further retard the release characteristics. Both the drug-resinate complex and microencapsulated drug resinate were suspended in a palatable aqueous suspension base and were evaluated for controlled release characteristic. Stability study indicated that elevated temperature did not alter the sustained release nature of the dosage form indicating that polymer membrane surrounding the core material remained intact throughout the storage period.