Development and validation of a simultaneous analytical method for non-steroidal therapeutic compounds in cosmetics using liquid chromatography-tandem mass spectrometry

Characterization and determination of Benvitimod, an unknown risk substance in cosmetics, using nuclear magnetic resonance spectroscopy and HPLC-MS/MS

Ultra-high performance liquid chromatography-tandem high-resolution mass spectrometry, combined with preparative chromatography and nuclear magnetic resonance spectroscopy, a new method for identifying unknown risk substances structure in cosmetics has been established. Moreover, HPLC-MS/MS was developed for the determination of benvitimod in cosmetics. The sample was collected in Ultra-high performance liquid chromatography-tandem high-resolution mass spectrometry, the molecular formula of the unknown was obtained as C₁₇ H₁₈ O₂ . After preparative chromatography enrichment and purification, the enriched compound was scanned by nuclear magnetic resonance spectroscopy, and the chemical structure of the unknown was confirmed as benvitimod. Subsequently, the separation was determined in multiple reaction monitoring mode. The results showed that the linearity of benvitimod was good in the range of 1∼100 μg/L with the correlation coefficient r² >0.999; the limit of detection and quantification were 0.02 mg/kg and 0.067 mg/kg; the precision and stability were good; the average recoveries were 104.2%, 108.2% and 108.7% for low, medium and high spiked concentrations. Forty batches of cosmetics were screened, of which two batches were detected with illegal addition of benvitimod at 2.48 g/kg and 3.13 g/kg. The method effectively solved the loopholes in regulation and provided a research basis for the qualitative identification of structurally unknown compounds in cosmetics. This article is protected by copyright. All rights reserved.