Evaluation of Some Excipients during Direct Tableting Processes Using their Flowability Index and Shearing Test

Abstract

Direct tableting is the most useful method of pharmaceutical compaction processes. In this process, the formulated mixtures need to have the suitable flowability in order to keep the uniformities of tablet quality and drug content. The standard formulation, defined in the excipient/corn starch in a 7/3 mixture with 20％ low-substituted hydroxypropylcellulose as a binder and 0.5％ magnesium stearate as a lubricant, was adapted for this process. Acetaminophen （drug content 1％） was used as a model drug. Anhydrous dibasic calcium phosphate, dibasic calcium phosphate hydrate, granulated lactose were examined for excipient.
Flow properties and shearing properties of excipient powders and formulated mixture powders were determined. These characteristics of formulated mixture powders would be related the deviation of tablet mass and the uniformity of drug content.