Glidant effect of hydrophobic and hydrophilic nanosilica on a cohesivepowder: comparison of different flow characterization techniques

• Main Authors: Ruzaidi, Fahmi Ahmad, Mandal, Uttam Kumar, Chatterjee, Bappaditya
• Format: Article
• Language: English; English; English
• Published: Elsevier 2017
• Subjects: RS Pharmacy and materia medica
• Online Access: http://irep.iium.edu.my/51875/25/51875_Glidant%20effect%20of%20hydrophobic.pdf; http://irep.iium.edu.my/51875/8/51875_Glidant%20effect%20of%20hydrophobic_SCOPUS.pdf; http://irep.iium.edu.my/51875/9/51875_Glidant%20effect%20of%20hydrophobic_WOS.pdf; http://irep.iium.edu.my/51875/; http://www.sciencedirect.com/science/article/pii/S1674200116300864

The methods used for flow characterization of a powder mass include the angle of repose (AOR), Carrindex (CI), and powder flow tester (PFT). The use of nanosilica as a flow modifier (glidant) is very com-mon in industry. This study aims to compare the glidant effect of hydrophobic and hydrophilic silica ona poorly flowable active pharmaceutical ingredient (ibuprofen) by different flow characterization tech-niques. Different percentages (0.5, 1.0, and 2.0 wt%) of both types of mixed silica–ibuprofen powders wereevaluated by the AOR, CI, bulk density, and PFT. The flow factor, effective angle of friction, and cohesionwere determined to explain the bulk powder properties. The results show that different types of silicashow different levels of flow property improvement, but the techniques do not equally discriminate thedifferences. Hydrophobic silica results in better improvement of the flow property than hydrophilic silica,probably because of its better surface coverage of silica on the host particles. Change of the bulk densitywith applied pressure was significant for the different powders. This study demonstrates that combiningseveral characterization methods provides a better understanding of bulk powder flow properties withrespect to powder–process relationships than a single flow indicator