title: Determination of residual solvents and investigation of their effect on ampicillin trihydrate crystal structure.
abstract: In the present work, the relationship between residual solvents concentration and ampicillin trihydrate crystals stability has been investigated. The amounts of residual solvents determined by GC, X-ray powder diffraction (XRPD) and Fourier transform infrared spectroscopy (FT-IR) were used for characterization of solid state. The obtained results have shown good relationship between concentration of methylene chloride (as a critical residue solvent) and degree of ampicillin trihydrate crystallinity. As with the increasing methylene chloride concentration in the sample the degree of crystallinity decreased after stability test. From this relationship, critical concentration of methylene chloride into the ampicillin trihydrate is obtained and the results can be used for improving the large-scale production of ampicillin trihydrate.
authors.affiliation: Department of Chemistry, Faculty of Science, Shahid Beheshti University, Tehran, Iran.
authors.forename: Saeed
authors.initials: S
authors.lastname: Nojavan
authors.forename: Alireza
authors.initials: A
authors.lastname: Ghassempour
authors.forename: Yosef
authors.initials: Y
authors.lastname: Bashour
authors.forename: Masoud Khalilian
authors.initials: MK
authors.lastname: Darbandi
authors.forename: Seyyed Hamid
authors.initials: SH
authors.lastname: Ahmadi
mesh_terms: D000667:Ampicillin / Q000032:analysis*; D003460:Crystallization; D012997:Solvents / Q000032:analysis*
chemical_list: D012997:Solvents; D000667:Ampicillin