Chen, Q, Zafar, U, Ghadiri, M orcid.org/0000-0003-0479-2845 et al. (1 more author) (2017) Assessment of Surface Caking of Powders Using the Ball Indentation Method. International Journal of Pharmaceutics, 521 (1-2). pp. 61-68. ISSN 0378-5173
Abstract
Powder caking is a ubiquitous problem, which could significantly decrease product quality and lead to economic losses. Hence it is important to know the conditions under which it occurs. The caking behaviour of three powder materials (PVP, HPC and CaHPO4) has been investigated by the ball indentation method (BIM) as affected by relative humidity (RH), temperature and time. The resistance to powder flow, as indicated by the hardness is measured by a ball indenting the powder bed surface. The surface hardness increases with increasing RH and temperature, indicating caking of the powder bed. Moreover, the temperature and RH show a coupled effect on powder caking. Irreversible caking is formed in PVP and HPC at 75% RH; the particles coalesce and the volume of powder bed is significantly reduced with time. However, the caking of CaHPO4 is reversible. To examine the caking mechanism of PVP and HPC, the critical glass transition RH is determined at 25 °C and 45 °C. The values are 63% and 53% RH for PVP and 61% and 50% RH for HPC, respectively. The glass transition moisture content in the ball indentation experiments is comparable with that determined by the dynamic vapor sorption measurement. BIM could be a fast and effective method for the assessment of powder surface caking.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2017 Published by Elsevier B.V. This is an author produced version of a paper published in International Journal of Pharmaceutics. Uploaded in accordance with the publisher's self-archiving policy. |
Keywords: | pharmaceutical powders; ball indentation; caking; moisture sorption; hardness; glass transition |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Chemical & Process Engineering (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 16 Feb 2017 12:05 |
Last Modified: | 16 Feb 2018 01:38 |
Published Version: | https://doi.org/10.1016/j.ijpharm.2017.02.033 |
Status: | Published |
Publisher: | Elsevier |
Identification Number: | 10.1016/j.ijpharm.2017.02.033 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:112460 |