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S 28 May 2016 Tablets & Capsules tablet analysis Tablet exam: Using dynamic compaction analysis to ensure successful formulations Joe Domingue and Michael Gamlen Gamlen Tableting This article describes a method for performing dynamic powder compaction analysis and a method for measuring the tensile fracture strength of tablets. By combining these two methods, you can better assess the tabletability of pharmaceutical powder formulations. A case study of orally disintegrating mini-tablets illustrates how to use the methods. cientists who are tasked with formulating and manu- facturing robust yet effective tablets face many chal- lenges. To help formulators overcome these challenges, Amidon and Sun recently proposed a USP monograph, <1062>, that defines the compaction design space (Figure 1) [1]. Nonetheless, optimizing tablets remains a big challenge for formulators, particularly during the early stages of development, when access to affordable and easy-to-use Figure 1 Three-dimensional compaction design space plot, as proposed by Amidon and Sun in USP draft monograph, "Tablet Compression Characterization <1062>" [1] 10 8 6 4 2 Tensile strength (MPa) Solid fraction 0.7 0.8 0.9 1.0 Compression pressure (MPa) 30 60 90 120 150 180 tools is limited. Specific challenges include identification of critical quality attributes (CQAs), characterization of the suitability and batch-to-batch tolerances of key excipi- ents, accessing API-excipient and excipient-excipient com- patibilities, and determining critical process parameters. This article highlights a comprehensive tablet exam protocol that combines dynamic powder compaction analysis with tensile fracture stress measurement of the resulting tablet. Together these measurements provide a fast, affordable, and highly predictive measure of the ulti- mate tabletability of a pharmaceutical powder formula- tion. They also provide unique real-time insights into the compaction process. The powder compaction triangle The CQAs of a powder to be compressed into a tablet are defined by the powder compaction triangle (Figure 2) [2]. They include but are not limited to: • Compressibility: The ability of a powder to undergo volume reduction under pressure. Figure 2 The powder compaction triangle Compaction pressure Compressibility Solid fraction Tensile strength Tabletability Compactibility