Study On Polymorphism Of Dexamethasone Sodium Phosphate

As one kind of important drugs of ardrenal cortex hormone, dexamethasone sodium phosphate (DSP) is widely used in clinical application. In industrial manufacture of DSP, crystallization is one of the most important process that decide the product quality. Therefore, in order to improve the quality of DSP crystal product, a systematic research of it was done in details.Reactive Crystallization of DSP crystal was investigated. The effects of solvent on crystal habit of DSP were investigated by SEM analysis.To obtain suitable CSD, the effect of operation conditions on product CSD was experimentally studied.The polymorphism of DSP crystal was investigated. Different crystal forms were prepared by reactive crystallization from three different solvents. Based on the measured data with IR spectra, DSC and powder XRD instruments, it has been proved that the products, which were produced from different solvents, belong to different crystal systems. The diffraction data for DSP crystal was collected by X-ray diffraction technique. Using the indexing program named TREOR90, the unit cell parameters and space group for DSP were obtained by the indexing of its diffraction data. It has been proved that these three products and the reported crystal belong to different crystal systems.The effects of solvent on crystal habits of DSP were investigated by SEM analysis. Using the software Materials Studio, the ideal crystal habit of DSP under vacuum condition was determined by the BFDH principle.Based on the theory of hydrogen bond, the solubility of DSP in different solvents and mixed solvents had been explained. The solubilities of DSP were measured by laser method and HPLC, and the effects of temperature and polymorphism on it were discussed.So far, no similar research report of the polymorphism of DSP crystal has been published yet.