Characterization of the trace-level impurities in the bulk drug citalopram by high-performance liquid chromatography/tandem multistage mass spectrometry.
Five trace impurities were detected in the bulk drug citalopram using high-performance liquid chromatography with UV detection. A simple and sensitive method suitable for liquid chromatography tandem multistage mass spectrometry (HPLC/MS(n)) analysis was developed. Using this method, the fragmentation behavior of citalopram and the impurities was investigated. Four impurities were rapidly characterized, and an unknown impurity was elucidated as 3-(3-dimethylaminopropyl)-N-(1-(3-dimethylaminopropyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-yl)-3-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carboxamide on the basis of the MS(n) and exact mass evidence, and the proposed structure was further confirmed by nuclear magnetic resonance (NMR) experiments after preparative isolation.
Department of Polymer Science & Engineering, Zhejiang University, Hangzhou 310027, China.
Cuirong
C
Sun
Hui
H
Xu
Yuanjiang
Y
Pan
Zhiquan
Z
Shen
Danhua
D
Wang
D018687:Antidepressive Agents, Second-Generation / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D015283:Citalopram / Q000032:analysis* / Q000737:chemistry*; D004340:Drug Contamination / Q000517:prevention & control*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram