title: Consolidation trend design based on Young's modulus of clarithromycin single crystals.
abstract: The key aim of this study was to determine single mechanical properties of clarithromycin polymorphic forms in order to select some of them as more suitable for the tableting process. For this purpose, AFM single-point nanoindentation was used. The Young's moduli of clarithromycin polymorphs were substantially different, which was consistent with the structural variations in their packing motifs. The presence of the adjacent layers, which can easily slide over each other due to the low energy barrier (the lowest Young's modulus was 0.25 GPa) resulted in better bulk compressibility (the highest Heckel coefficient) of clarithromycin Form I. We also addressed the importance of tip geometry screening because the stress during the force mode often results in tip apex fracture. Even the initial manufacture of the diamond-coated tips can result in defects such as double-apex tips.
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia. biljana.jankovic@ffa.uni-lj.si
authors.forename: B
authors.initials: B
authors.lastname: Janković
authors.forename: M
authors.initials: M
authors.lastname: Skarabot
authors.forename: Z
authors.initials: Z
authors.lastname: Lavrič
authors.forename: I
authors.initials: I
authors.lastname: Ilić
authors.forename: I
authors.initials: I
authors.lastname: Muševič
authors.forename: S
authors.initials: S
authors.lastname: Srčič
authors.forename: O
authors.initials: O
authors.lastname: Planinšek
mesh_terms: D002626:Chemistry, Pharmaceutical; D017291:Clarithromycin / Q000737:chemistry*; D019245:Compressive Strength; D003460:Crystallization; D055119:Elastic Modulus; D018625:Microscopy, Atomic Force; D008956:Models, Chemical; D015394:Molecular Structure; D036103:Nanotechnology; D013314:Stress, Mechanical; D013499:Surface Properties; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods; D013718:Tensile Strength
chemical_list: D013607:Tablets; D017291:Clarithromycin
keywords: Atomic force microscopy; Clarithromycin; Nanoindentation; Polymorphism; Young's modulus