Can we predict hygroscopicity of a tablet from its starting materials?


Michael Gamlen
Gamlen Tableting Ltd, Biocity Nottingham, Nottingham NGI IGF, UK

M Majumder
M2M Pharmaceuticals Ltd, Science & Technology Centre, University of Reading, Whiteknights Road, Earley Gate,
Reading RG6 6BZ, UK


Dynamic vapour sorption (DVS) is used to measure the change in weight of a sample on exposure to various relative humidity conditions (% RH) at a fixed temperature. It is widely used to predict the stability of pharmaceuticals as well as in a wide range of other industries. The purpose of this study was to check if the sorption profile of tablet starting materials can be used to predict the properties of a finished tablet, and whether the

Early stage characterisation of the water uptake properties of a formulation can provide valuable insight into formulation selection; the impact of process selection on the water uptake properties of a formulation have not been reported.


A generic wet granulated tablet formulation was prepared from lactose EP, microcrystalline cellulose EP, starch EP, polyvinylpyrrolidone EP and paracetamol EP. Paracetamol (Mallincrokdt) was granulated (150 g scale, Kenwood mixer) with corn starch BP (2%), microcrystalline cellulose (10%), and lactose EP (10%) and PVP (supplier) solution (1%), wet sieved (4mm), dried to a moisture content of 1.2% and lubricant blended (1% sodium stearyl fumarate,JRS, Pruv) for 3 minutes in Turbula blender. The blended granule c=was compressed using the Gamlen© D Series Dynamic Powder Compaction Analyzer at a range of compaction forces from 200 – 500 kg using the 3 rnm and 6 mm punch and die sets and tablet weights of 20 and 100 mg respectively.

DVS experiments were carried out at 25.0 0 C (± 0. I O C) with a mass of ca. 20 mg for each component using DVS Advantage (SMS). Each experiment was set to run from 0 to 90% RH as a 10% increment at each step and then 10% decrement whilst desorbing. The percentage of change in weight is obtained at varying % RH and compared. A theoretical model was prepared based on the sorption data from the participating components. and their respective ratio used in the tablet. The theoretical data were compared with the experimental data. The DVS program was repeated on a formulation sample, prior to compression.


Stability of pharmaceutical products and its packaging remain an important and key parameter to have a successful product. Therefore, understanding the sorption profile of each component and their final formulation and dosage form remain very important requisites. We have shown that the effect of humidity on formed granules and tablets cannot be assumed to be predictable but should be characterised on a case by case basis.

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(filed under AAPS posters 14 November 2016, in download library)

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