Optimization of HS-GC-FID-MS Method for Residual Solvent Profiling in Active Pharmaceutical Ingredients Using DoE

Within this research, a headspace (HS) gas chromatography-flame ionization detector-mass spectrometry method was developed for profiling of residual solvents (RSs) in active pharmaceutical ingredients (APIs). Design of experiment was used for optimization of sample preparation, as well as for robustness testing of the method. HS equilibration temperature and dilution medium were detected as parameters with greater impact on the sensitivity, compared with the time used for equilibration of the samples. Regardless of the sample solubility, the use of water for sample preparation was found to be crucial for better sensitivity. The use of a well-designed strategy for method development and robustness testing, additional level of identification confidence, as well as use of internal standard provided a strong and reliable analytical tool for API fingerprinting, thus enabling the authentication of the substance based on the RS profile.