Impact breakage of pharmaceutical tablets

Publication date: 30 January 2018 Source:International Journal of Pharmaceutics, Volume 536, Issue 1 Author(s): C. Hare, T. Bonakdar, M. Ghadiri, J. Strong Tablets are the most common solid dosage form of pharmaceutical active ingredients due to their ease of use. Their dissolution behaviour depends on the particle size distribution and physicochemical properties of the formulation, and the compression process, which need to be optimised for producing consistently robust tablets, as weaker tablets are often prone to breakage during production, transport and end use. Tablet strength is typically determined by diametric compression and friability tests. The former gives rise to propagation of a crack on a plane along the compression axis, whilst the latter, carried out in a rotating drum, incurs surface damage and produces chips and debris. These tests produce different measures of strength, neither of which have been correlated with mechanical properties that are accountable for breakage, i.e. hardness, elastic modulus and fracture toughness. We propose a new method based on single tablet impact testing, following the work of Ghadiri and Zhang, 2002, who analysed particle damage by propagation of sub-surface lateral cracks and identified the fundamental form accountable for impact surface damage to be a lumped parameter related to hardness and fracture toughness. Microindentation, carried out separately, to determine fracture toughness led to complete failure of the tabl...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research