title: Vibrational spectroscopic study of polymorphism and polymorphic transformation of the anti-viral drug lamivudine.
abstract: Vibrational spectra of hydrated and anhydrous lamivudines, and also the dynamic process of polymorphic transformation have been characterized by Fourier transform infrared (FT-IR) and Raman spectroscopic techniques. The vibrational modes of both polymorphic lamivudines are assigned. FT-IR and Raman spectral results show that the interaction between crystalline water and lamivudine molecular has an important effect on the molecular vibration motions of polymorphic lamivudines. The two characteristic Raman peaks at 783 and 798 cm(-1) represent hydrated and anhydrous lamivudine respectively. The relationship between changes of two characteristic peak normalized areas and heating time could be fitted with single exponential functions, and the dynamic information of polymorphic transformation of lamivudine drug is obtained. The decay rate of characteristic peak for hydrated lamivudine and the growth rate of that for anhydrous lamivudine are consistent during dehydration transformation process. The reported results provide us important benchmark for qualitatively monitoring different polymorphic drugs and also establishing the corresponding model for the polymorphic transformation of drugs in related pharmaceutical research fields.
authors.affiliation: Centre for THz Research, China Jiliang University, Hangzhou 310018, China. Electronic address: yongdu@cjlu.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Du
authors.affiliation: Centre for THz Research, China Jiliang University, Hangzhou 310018, China.
authors.forename: Huili
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
authors.forename: Jiadan
authors.initials: J
authors.lastname: Xue
authors.affiliation: School of Pharmacy, Anhui Medical University, Hefei 230032, China.
authors.forename: Wenjian
authors.initials: W
authors.lastname: Tang
authors.affiliation: Centre for THz Research, China Jiliang University, Hangzhou 310018, China.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Fang
authors.affiliation: Centre for THz Research, China Jiliang University, Hangzhou 310018, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China.
authors.forename: Yafang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Centre for THz Research, China Jiliang University, Hangzhou 310018, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Hong
mesh_terms: D000998:Antiviral Agents / Q000737:chemistry*; D019259:Lamivudine / Q000737:chemistry*; D008958:Models, Molecular; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman; D014867:Water / Q000737:chemistry
chemical_list: D000998:Antiviral Agents; D014867:Water; D019259:Lamivudine
keywords: Anhydrous; Fourier transform infrared spectrum; Hydrated; Lamivudine; Polymorphic transformation; Raman spectrum