The difference of drug crystal type will lead to the difference of clinical efficacy, related to drug safety and other issues. powder X-ray diffraction (PXRD), as one of the methods for the study of drug polymorphism, has the advantages of not destroying the sample and being simple to operate, and is currently a major method for the qualitative and quantitative analysis of drug polymorphism.

The manifestation of PXRD in the qualitative application of drug polycrystalline form

① Identification of polycrystalline type of raw material.

PXRD identification of API polycrystalline form is to obtain the crystal structure data of API from the existing database and generate the corresponding simulation map, which can be compared with the measured map to quickly determine what the polycrystalline form of the drug is. 

② Identification of raw materials in solid preparations.

The effect of excipients or small molecular additives on the polycrystalline form of raw materials in solid preparations was investigated by PXRD.  The grinding method of the solid preparation formed by the API and excipients or small molecule additives will also change the crystal shape of the API, but the diffraction peak of the API is not interfered by the diffraction peak of the excipients or small molecule additives in the powder profile.

                                                                          Powder X-ray Diffractometer