VALIDATION OF LC-MS/MS METHOD FOR DETERMINATION OF CYPROHEPTADINE IN DIETARY SUPPLEMENTS

Aims: A rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was validated for determination of prohibited cyproheptadine hydrochloride (CP) in dietary supplements. Methods: CP was extracted by sonication in methanol for 30 min. The chromatography separation of CP took place on C18 column (100 mm x 2.1 mm, 1.8 µm) with gradient mobile phase of both of acetonitrile and water containing 0.1% formic acid. Multiple reaction monitoring (MRM) in the positive mode was used to quantify and confirm CP at m/z 288.2/191.1  and 288.1/96.0, respectively. Results: The method was validated according to the AOAC requirements. The linearity ranges were found from 0.1 to 50 ng. mL-1 of CP (R2 = 1). The limit of detection and limit of quantification were 1.5 ng/g or ng/mL and 5 ng/g or ng/mL, respectively. The accuracy was within the range from 92 to 99%, with the relative standard deviation (RSD%) of 2.0-5.9%. Conclusion: The validated parameters have met the requirement of Association of Official Agricultural Chemists (AOAC). This reliable method would be useful for the monitoring of cyproheptadine in dietary supplements.