title: Crystal structure and surface properties of an investigational drug--a case study.
abstract: In this study we investigate the correlations between the single crystal structure, the crystal habitat and morphology, and surface energetics of an investigational pharmaceutical compound. Crystal structure of this investigational pharmaceutical solid has been solved from single crystal X-ray analysis. Crystallographic data are as follows: triclinic, P1 (no. 1), a = 6.1511 (8) A, b = 13.5004 (18) A, c = 17.417 (2) A, alpha = 68.259 (2) degrees, beta = 80.188 (2) degrees, gamma = 82.472 (2) degrees, V = 1320.2 (3) A(3), Z = 2. The external morphology of this crystalline solid was predicted by molecular modelling using attachment energies to be thin-plate like with a dominant face (001). The predicted morphology was confirmed by scanning electron micrographs (SEM) and the Miller Index of the dominant face was complemented by X-ray powder diffraction (XRPD) method. The microscopic layering structures of crystals and surface stability of the dominant faces were investigated using atomic force microscopy (AFM). Contact angle measurement showed that the surface of the dominant face is hydrophilic as predicted from crystal structure.
authors.affiliation: Pharmaceutical Research and Development, Merck Research Laboratories, Merck and Co. Inc., West Point, PA 19426, USA. yuanhon_kiang@merck.com
authors.forename: Y-H
authors.initials: YH
authors.lastname: Kiang
authors.forename: H Galen
authors.initials: HG
authors.lastname: Shi
authors.forename: David J
authors.initials: DJ
authors.lastname: Mathre
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Dina
authors.initials: D
authors.lastname: Zhang
authors.forename: Santipharp
authors.initials: S
authors.lastname: Panmai
mesh_terms: D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D015507:Drugs, Investigational / Q000032:analysis* / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D013499:Surface Properties; D013678:Technology, Pharmaceutical / Q000379:methods*
chemical_list: D015507:Drugs, Investigational