Study on impurities in naringin extracted from Citrus grandis 'tomentosa'.

Objective: To investigate the impurities in naringin extracted from Citrus grandis 'Tomentosa'.Methods: High performance liquid chromatographies coupled with photodiode array and electrospray ionization mass spectrometry detectors(HPLC-PDA/ESI-MS/MS)were applied to investigate the impurities,and their structures were elucidated by spectral data analyses.Quantification was carried out by main component self-compare with correction factor according to ICH guidelines.Results: Rhoifolin and neoeriocitrin were identified as major impurities.The correction factors of rhoifolin and neoeriocitrin were 1.82 and 1.02,respectively tested by HPLC method.The content of rhoifolin ranged from 0.742% to 0.926%,and the content of neoeriocitrin ranged from 0.335% to 0.464%.The gross impurities were less than 1.5%.Conclusion: The categories and quantities of impurities in naringin product are relatively stable.The research provides a way of specification and verification for the analysis of impurities and objective evidence for security assessment of naringin product.