title: [Approach to the crystalline characteristics of ceftezole sodium].
abstract: OBJECTIVE
  To study the crystalline characteristics of ceftezole sodium.
  
  
  METHODS
  Ceftezole sodium crystals were obtained from different solvents. X-ray diffraction, DSC, TGA, etc were used to analyze the crytals.
  
  
  RESULTS
  Ceftezole sodium crystal was easily obtained in isopropanol-water mixture. It consists of ceftizole sodium monohydrate, which consists of type I and type II two different crystal forms. Powder X-ray diffraction patterns showed differences between type I and the type II crystal forms. Peaks at 8 degrees and 18 degrees in diffractograms of the type I, but at 9 degrees and 18.6 degrees in the type II could be observed. Water molecules in different crystal forms had different combining condition. They lost during 35-117 degrees C in the type I form, but lost during 110-160 degrees C in the type II form.
  
  
  CONCLUSIONS
  Structure of ceftizole sodium monohydrate crystal obtained in different circumstance could be some vary, which influence upon the thermal stability of the compound. The type I crystal form is more stable than the type II.
authors.affiliation: National Institute for the Control of Pharmaceutical and Biological Products, Beijing 100050, China. hucq@nicpbp.org.cn
authors.forename: Chang-qin
authors.initials: CQ
authors.lastname: Hu
authors.forename: Shuang-hong
authors.initials: SH
authors.lastname: Cheng
authors.forename: Lu
authors.initials: L
authors.lastname: Lu
mesh_terms: D002437:Cefazolin / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000145:classification; D003460:Crystallization; D018360:Crystallography, X-Ray; D004355:Drug Stability; D008968:Molecular Conformation; D015394:Molecular Structure
chemical_list: C012811:ceftezole; D002437:Cefazolin