Single-step coprocessing of cohesive powder via mechanical dry coating for direct tablet compression

Li Qu, Peter James Stewart, Karen P. Hapgood, Satu Lakio, David A.V. Morton, Qi (Tony) Zhou

Research output: Contribution to journalArticleResearchpeer-review

33 Citations (Scopus)


This study aims at testing the feasibility of a single-step coating process to produce a powder formulation of active and inactive ingredients for direct compression. A cohesive ibuprofen powder was coprocessed with a coating material, a binder (polyvinylpyrrolidone K25), and a superdisintegrant (crospovidone). Magnesium stearate (MgSt), L-leucine, and silica were selected as coating materials (1% w/w). A coprocessed powder without any coating material was employed as a control. Coating with MgSt, L-leucine, or silica produced significantly improved powder flow in comparison to the control batch. Robust tablets were produced from the processed powders for each coating material. The tablets compacted using the coated powders with MgSt or L-leucine also exhibited significantly lower tablet ejection forces than the control batch, demonstrating their lubrication effect. Furthermore, the disintegration time and dissolution rates of these tablets made of the formulations coprocessed with lubricants were enhanced, even for those coated with the hydrophobic material such as MgSt that has been previously reported to inhibit dissolution. However, the tablets made with silica-coated powders would not disintegrate. This study indicated the feasibility of a single-step dry coating process to produce powders with both flow-aid and lubrication effects, which are suitable for direct compression.
Original languageEnglish
Pages (from-to)159-167
Number of pages9
JournalJournal of Pharmaceutical Sciences
Issue number1
Publication statusPublished - 1 Jan 2017


  • direct compression
  • dissolution
  • fine cohesive powder
  • flowability
  • lubrication
  • mechanical dry coating

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