Evaluation of controlled-release polar lipid microparticles

• Published in: International journal of pharmaceutics Vol. 244; no. 1; pp. 151 - 161
• Main Authors: Savolainen, Marja, Khoo, Cynthia, Glad, Håkan, Dahlqvist, Carina, Juppo, Anne Mari
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.09.2002; Elsevier
• Subjects: Antihypertensive Agents - administration & dosage; Antihypertensive Agents - analysis; Biological and medical sciences; Chemistry, Pharmaceutical - methods; Chromatography, High Pressure Liquid; Controlled release; Delayed-Action Preparations; Evaluation Studies as Topic; Excipients - classification; Felodipine; Felodipine - administration & dosage; Felodipine - analysis; General pharmacology; Lipids; Medical sciences; Microparticles; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Polar lipids; Solid dispersion; Spectroscopy, Fourier Transform Infrared; Spray chilling; Tablets; Spray chilling; Solid dispersion; Polar lipids; Controlled release; Microparticles; Felodipine; Microcrystalline material; Particle size; Pharmaceutical technology; Controlled release form; Cellulose; Vehicle(excipient); Molecular interaction; Lipids; Drug carrier; Crystallinity; Hydrophobicity; In vitro; Property formulation relationship; Dosage form; Microparticle; Active ingredient; Tablet; Dihydropyridine derivatives; Release; Physicochemical properties; Physical structure
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/S0378-5173(02)00325-3

The aim of the present study was to prepare controlled-release tablets of poorly-soluble drug, felodipine, and various erodable lipophilic excipients. Spray chilling was used to formulate the drug and the excipients into solid dispersion microparticles, which were then compressed. The microparticles were characterised by Fourier transform infrared spectroscopy, hot-stage microscopy, scanning electron microscopy, and image analysis. The amine and the carbonyl groups of felodipine formed hydrogen bonds with the carriers. The shape of the particles was spherical with the median particle diameter ranging from 25 to 35 μm. Surprisingly, the degree of crystallinity in felodipine and the ease of tablet disintegration played a more significant role on the felodipine dissolution rate than the matrix lipophilicity. Felodipine release rate was slowest from the least lipophilic tablets.