Influence of Avicel PH-301 on the compressibility of alpha-methyldopa and phenobarbitone in direct compression

• Published in: Drug development and industrial pharmacy Vol. 26; no. 9; p. 1013
• Main Authors: Siaan, M, Pintye-Hódi, K, Szabó-Révész, P, Kása, Jr, P, Erõs, I
• Format: Journal Article
• Language: English
• Published: England 01.01.2000
• Subjects: Anticonvulsants - chemistry; Antihypertensive Agents - chemistry; Cellulose - chemistry; Chemical Phenomena; Chemistry, Pharmaceutical; Chemistry, Physical; Compressive Strength; Elasticity; Excipients - chemistry; Friction; Hypnotics and Sedatives - chemistry; Lubrication; Methyldopa - chemistry; Phenobarbital - chemistry; Stearic Acids; Tablets; Technology, Pharmaceutical
• ISSN: 0363-9045
• DOI: 10.1081/DDC-100101331

The aim of this work was to investigate the compressibility behavior of alpha-methyldopa and phenobarbitone using a Korsch EK0 instrumented eccentric tablet machine, with force-time and force-displacement curves constructed and applied to calculate different compressional values to study the compressional behavior. The results of this work revealed a difference in compressibility behavior between the two drugs during the compressional process. alpha-Methyldopa gave an abnormal compressional curve with high friction in the pre- and postcompressional phases. A residual force could be seen on the lower punch. Furthermore, capping and sticking were observed visually during tablet pressing, indicating poor compressibility behavior. In the case of phenobarbitone, no friction was observed in the precompressional phase, but there was higher friction in the postcompressional phase, especially in the ejection phase. The compressibility of the drugs was improved by the addition of Avicel PH-301 and magnesium stearate.