Quantitative determination of fluoxetine hydrochloride in conventional solid oral formulations using 19F qNMR method
LI Zeng-xin
ZHOU Xiao-li
LIU Wan-hui
YIN Li-hui
Abstract：Objective:To establish a 19F qNMR quantitative method for determining the content of fluoxetine hydrochloride in conventional solid oral formulations. Methods:4-Fluorocinnamic acid was used as the internal standard and dimethyl sulfoxide as the solvent. The Bruker Avance Ⅲ HD 500 MHz nuclear magnetic resonance spectrometer was applied using a pulse sequence of zgfhigqn. 2. The 19F nuclear magnetic resonance spectra ( 19F NMR spectrum) were collected at a constant temperature of 25℃,and a relaxation delay time ( D1 ) of 10 seconds. The absolute contents of fluoxetine hydrochloride in conventional solid oral formulations were determined. Result:Quantitative signals were obtained from the signals at δ-60 ppm of fluoxetine hydrochloride andδ-110.44 ppm of 4-fluorocinnamic acid. In parallel configuration of 6 test sample solutions,the RSD for repeatability is less than 2％. A standard curve for the mass of the sample based on its peak area was plotted. The linear range of fluoxetine hydrochloride is 2.5 mg to 7.5 mg,with a correlation coefficient of 0.9996. The recovery rate results are all between 98％ and 102％. The RSD for stability and precision within 60 hours is less than 1.2％. The quantitative results of 19F qNMR are basically consistent with the HPLC content determination results. Conclusion:According to the certification of traditional Chinese medicine,the 19F qNMR method can be used to determine the absolute content of fluoxetine hydrochloridec in onventional solid oral formulations.
Keywords：fluoxetine hydrochloride4-fluorocinnamic acidabsolute content determination19F qNMRmultiple solid formulations
Publication Date：2025-01-14
Online Publishing Date：2026-08-14(First online date of this platform, not the publication date of the document)
Pages：5( 89-93 )