Insights into flibanserin oxidative stress degradation pathway: in silico – in vitro toxicity assessment of its degradates†
Characterization of the degradation products of pharmaceutical drugs is essential to assess their safety. As these degradation products may have significant effects on the human physiological system. This study aims to isolate, characterize, and confirm the structures of flibanserin oxidative degradation products and evaluate their safety using in silico toxicity prediction that is confirmed by in vitro SRB cytotoxicity assay. Two degradation products were formed after oxidative degradation of flibanserin followed by their isolation then characterization by 1H NMR and LC-MS/MS techniques. The parent drug and its degradation products were resolved using HPLC and their chromatographic separation was achieved on a reversed-phase Eclipse XDB C18 column (4.6 × 150 mm, 5 μm). The elution was performed using isocratic mode with a flow rate of 1 mL min−1 and detected at 255 nm. The method was validated according to the International Conference on Harmonization (ICH) guidelines and was linear over the concentration range of 0.1–10 μg mL−1. Besides, the in silico toxicity prediction studies suggested no toxicity potential of the degradation products, which was confirmed using in vitro SRB cytotoxicity assays to evaluate the safety profile of these degradation products.